79 files changed, 8704 insertions, 5200 deletions
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AggregationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AggregationImpl.java
new file mode 100644
index 00000000..542f3c40
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AggregationImpl.java
@@ -0,0 +1,343 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Aggregation;
+import org.eclipse.viatra.solver.language.solverLanguage.AggregationOp;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Aggregation</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.AggregationImpl#getOp <em>Op</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.AggregationImpl#getBody <em>Body</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.AggregationImpl#getCondition <em>Condition</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class AggregationImpl extends ExpressionImpl implements Aggregation
+{
+  /**
+   * The default value of the '{@link #getOp() <em>Op</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOp()
+   * @generated
+   * @ordered
+   */
+  protected static final AggregationOp OP_EDEFAULT = AggregationOp.ONLY;
+  /**
+   * The cached value of the '{@link #getOp() <em>Op</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOp()
+   * @generated
+   * @ordered
+   */
+  protected AggregationOp op = OP_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getBody()
+   * @generated
+   * @ordered
+   */
+  protected Expression body;
+  /**
+   * The cached value of the '{@link #getCondition() <em>Condition</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getCondition()
+   * @generated
+   * @ordered
+   */
+  protected Expression condition;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected AggregationImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.AGGREGATION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public AggregationOp getOp()
+  {
+    return op;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setOp(AggregationOp newOp)
+  {
+    AggregationOp oldOp = op;
+    op = newOp == null ? OP_EDEFAULT : newOp;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.AGGREGATION__OP, oldOp, op));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getBody()
+  {
+    return body;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
+  {
+    Expression oldBody = body;
+    body = newBody;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.AGGREGATION__BODY, oldBody, newBody);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setBody(Expression newBody)
+  {
+    if (newBody != body)
+    {
+      NotificationChain msgs = null;
+      if (body != null)
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.AGGREGATION__BODY, null, msgs);
+      if (newBody != null)
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.AGGREGATION__BODY, null, msgs);
+      msgs = basicSetBody(newBody, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.AGGREGATION__BODY, newBody, newBody));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getCondition()
+  {
+    return condition;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetCondition(Expression newCondition, NotificationChain msgs)
+  {
+    Expression oldCondition = condition;
+    condition = newCondition;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.AGGREGATION__CONDITION, oldCondition, newCondition);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setCondition(Expression newCondition)
+  {
+    if (newCondition != condition)
+    {
+      NotificationChain msgs = null;
+      if (condition != null)
+        msgs = ((InternalEObject)condition).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.AGGREGATION__CONDITION, null, msgs);
+      if (newCondition != null)
+        msgs = ((InternalEObject)newCondition).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.AGGREGATION__CONDITION, null, msgs);
+      msgs = basicSetCondition(newCondition, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.AGGREGATION__CONDITION, newCondition, newCondition));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.AGGREGATION__BODY:
+        return basicSetBody(null, msgs);
+      case SolverLanguagePackage.AGGREGATION__CONDITION:
+        return basicSetCondition(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.AGGREGATION__OP:
+        return getOp();
+      case SolverLanguagePackage.AGGREGATION__BODY:
+        return getBody();
+      case SolverLanguagePackage.AGGREGATION__CONDITION:
+        return getCondition();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.AGGREGATION__OP:
+        setOp((AggregationOp)newValue);
+        return;
+      case SolverLanguagePackage.AGGREGATION__BODY:
+        setBody((Expression)newValue);
+        return;
+      case SolverLanguagePackage.AGGREGATION__CONDITION:
+        setCondition((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.AGGREGATION__OP:
+        setOp(OP_EDEFAULT);
+        return;
+      case SolverLanguagePackage.AGGREGATION__BODY:
+        setBody((Expression)null);
+        return;
+      case SolverLanguagePackage.AGGREGATION__CONDITION:
+        setCondition((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.AGGREGATION__OP:
+        return op != OP_EDEFAULT;
+      case SolverLanguagePackage.AGGREGATION__BODY:
+        return body != null;
+      case SolverLanguagePackage.AGGREGATION__CONDITION:
+        return condition != null;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (op: ");
+    result.append(op);
+    result.append(')');
+    return result.toString();
+  }
+} //AggregationImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PolarityImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ArgumentImpl.java
index 7c2ae07d..d8bf8d91 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PolarityImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ArgumentImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -7,24 +7,24 @@ import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.Polarity;
+import org.eclipse.viatra.solver.language.solverLanguage.Argument;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Polarity</b></em>'.
+ * An implementation of the model object '<em><b>Argument</b></em>'.
 * <!-- end-user-doc -->
 *
 * @generated
 */
-public class PolarityImpl extends MinimalEObjectImpl.Container implements Polarity
+public class ArgumentImpl extends MinimalEObjectImpl.Container implements Argument
 {
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected PolarityImpl()
+  protected ArgumentImpl()
  {
    super();
  }
@@ -37,7 +37,7 @@ public class PolarityImpl extends MinimalEObjectImpl.Container implements Polari
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.POLARITY;
+    return SolverLanguagePackage.Literals.ARGUMENT;
  }
-} //PolarityImpl
+} //ArgumentImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PatternBodyImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ArgumentListImpl.java
index 5cd03fbf..8c16fb4f 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PatternBodyImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ArgumentListImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -17,41 +17,41 @@ import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
 import org.eclipse.emf.ecore.util.EObjectContainmentEList;
 import org.eclipse.emf.ecore.util.InternalEList;
-import org.eclipse.viatra.solver.language.solverLanguage.Constraint;
+import org.eclipse.viatra.solver.language.solverLanguage.Argument;
-import org.eclipse.viatra.solver.language.solverLanguage.PatternBody;
+import org.eclipse.viatra.solver.language.solverLanguage.ArgumentList;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Pattern Body</b></em>'.
+ * An implementation of the model object '<em><b>Argument List</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PatternBodyImpl#getConstraints <em>Constraints</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ArgumentListImpl#getArguments <em>Arguments</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class PatternBodyImpl extends MinimalEObjectImpl.Container implements PatternBody
+public class ArgumentListImpl extends MinimalEObjectImpl.Container implements ArgumentList
 {
  /**
-   * The cached value of the '{@link #getConstraints() <em>Constraints</em>}' containment reference list.
+   * The cached value of the '{@link #getArguments() <em>Arguments</em>}' containment reference list.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getConstraints()
+   * @see #getArguments()
   * @generated
   * @ordered
   */
-  protected EList<Constraint> constraints;
+  protected EList<Argument> arguments;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected PatternBodyImpl()
+  protected ArgumentListImpl()
  {
    super();
  }
@@ -64,7 +64,7 @@ public class PatternBodyImpl extends MinimalEObjectImpl.Container implements Pat
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.PATTERN_BODY;
+    return SolverLanguagePackage.Literals.ARGUMENT_LIST;
  }
  /**
@@ -73,13 +73,13 @@ public class PatternBodyImpl extends MinimalEObjectImpl.Container implements Pat
   * @generated
   */
  @Override
-  public EList<Constraint> getConstraints()
+  public EList<Argument> getArguments()
  {
-    if (constraints == null)
+    if (arguments == null)
    {
-      constraints = new EObjectContainmentEList<Constraint>(Constraint.class, this, SolverLanguagePackage.PATTERN_BODY__CONSTRAINTS);
+      arguments = new EObjectContainmentEList<Argument>(Argument.class, this, SolverLanguagePackage.ARGUMENT_LIST__ARGUMENTS);
    }
-    return constraints;
+    return arguments;
  }
  /**
@@ -92,8 +92,8 @@ public class PatternBodyImpl extends MinimalEObjectImpl.Container implements Pat
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PATTERN_BODY__CONSTRAINTS:
+      case SolverLanguagePackage.ARGUMENT_LIST__ARGUMENTS:
-        return ((InternalEList<?>)getConstraints()).basicRemove(otherEnd, msgs);
+        return ((InternalEList<?>)getArguments()).basicRemove(otherEnd, msgs);
    }
    return super.eInverseRemove(otherEnd, featureID, msgs);
  }
@@ -108,8 +108,8 @@ public class PatternBodyImpl extends MinimalEObjectImpl.Container implements Pat
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PATTERN_BODY__CONSTRAINTS:
+      case SolverLanguagePackage.ARGUMENT_LIST__ARGUMENTS:
-        return getConstraints();
+        return getArguments();
    }
    return super.eGet(featureID, resolve, coreType);
  }
@@ -125,9 +125,9 @@ public class PatternBodyImpl extends MinimalEObjectImpl.Container implements Pat
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PATTERN_BODY__CONSTRAINTS:
+      case SolverLanguagePackage.ARGUMENT_LIST__ARGUMENTS:
-        getConstraints().clear();
+        getArguments().clear();
-        getConstraints().addAll((Collection<? extends Constraint>)newValue);
+        getArguments().addAll((Collection<? extends Argument>)newValue);
        return;
    }
    super.eSet(featureID, newValue);
@@ -143,8 +143,8 @@ public class PatternBodyImpl extends MinimalEObjectImpl.Container implements Pat
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PATTERN_BODY__CONSTRAINTS:
+      case SolverLanguagePackage.ARGUMENT_LIST__ARGUMENTS:
-        getConstraints().clear();
+        getArguments().clear();
        return;
    }
    super.eUnset(featureID);
@@ -160,10 +160,10 @@ public class PatternBodyImpl extends MinimalEObjectImpl.Container implements Pat
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PATTERN_BODY__CONSTRAINTS:
+      case SolverLanguagePackage.ARGUMENT_LIST__ARGUMENTS:
-        return constraints != null && !constraints.isEmpty();
+        return arguments != null && !arguments.isEmpty();
    }
    return super.eIsSet(featureID);
  }
-} //PatternBodyImpl
+} //ArgumentListImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ParameterImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AssertionImpl.java
index 6281c4bc..8165b62e 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ParameterImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AssertionImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -10,55 +10,53 @@ import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.InternalEObject;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.Parameter;
+import org.eclipse.viatra.solver.language.solverLanguage.Assertion;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Symbol;
-import org.eclipse.viatra.solver.language.solverLanguage.Variable;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Parameter</b></em>'.
+ * An implementation of the model object '<em><b>Assertion</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ParameterImpl#getVariable <em>Variable</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.AssertionImpl#getBody <em>Body</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ParameterImpl#getType <em>Type</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.AssertionImpl#getRange <em>Range</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class ParameterImpl extends MinimalEObjectImpl.Container implements Parameter
+public class AssertionImpl extends StatementImpl implements Assertion
 {
  /**
-   * The cached value of the '{@link #getVariable() <em>Variable</em>}' containment reference.
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getVariable()
+   * @see #getBody()
   * @generated
   * @ordered
   */
-  protected Variable variable;
+  protected Expression body;
  /**
-   * The cached value of the '{@link #getType() <em>Type</em>}' containment reference.
+   * The cached value of the '{@link #getRange() <em>Range</em>}' containment reference.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getType()
+   * @see #getRange()
   * @generated
   * @ordered
   */
-  protected Symbol type;
+  protected Expression range;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected ParameterImpl()
+  protected AssertionImpl()
  {
    super();
  }
@@ -71,7 +69,7 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.PARAMETER;
+    return SolverLanguagePackage.Literals.ASSERTION;
  }
  /**
@@ -80,9 +78,9 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
   * @generated
   */
  @Override
-  public Variable getVariable()
+  public Expression getBody()
  {
-    return variable;
+    return body;
  }
  /**
@@ -90,13 +88,13 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
   * <!-- end-user-doc -->
   * @generated
   */
-  public NotificationChain basicSetVariable(Variable newVariable, NotificationChain msgs)
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
  {
-    Variable oldVariable = variable;
+    Expression oldBody = body;
-    variable = newVariable;
+    body = newBody;
    if (eNotificationRequired())
    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PARAMETER__VARIABLE, oldVariable, newVariable);
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.ASSERTION__BODY, oldBody, newBody);
      if (msgs == null) msgs = notification; else msgs.add(notification);
    }
    return msgs;
@@ -108,20 +106,20 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
   * @generated
   */
  @Override
-  public void setVariable(Variable newVariable)
+  public void setBody(Expression newBody)
  {
-    if (newVariable != variable)
+    if (newBody != body)
    {
      NotificationChain msgs = null;
-      if (variable != null)
+      if (body != null)
-        msgs = ((InternalEObject)variable).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PARAMETER__VARIABLE, null, msgs);
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.ASSERTION__BODY, null, msgs);
-      if (newVariable != null)
+      if (newBody != null)
-        msgs = ((InternalEObject)newVariable).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PARAMETER__VARIABLE, null, msgs);
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.ASSERTION__BODY, null, msgs);
-      msgs = basicSetVariable(newVariable, msgs);
+      msgs = basicSetBody(newBody, msgs);
      if (msgs != null) msgs.dispatch();
    }
    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PARAMETER__VARIABLE, newVariable, newVariable));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.ASSERTION__BODY, newBody, newBody));
  }
  /**
@@ -130,9 +128,9 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
   * @generated
   */
  @Override
-  public Symbol getType()
+  public Expression getRange()
  {
-    return type;
+    return range;
  }
  /**
@@ -140,13 +138,13 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
   * <!-- end-user-doc -->
   * @generated
   */
-  public NotificationChain basicSetType(Symbol newType, NotificationChain msgs)
+  public NotificationChain basicSetRange(Expression newRange, NotificationChain msgs)
  {
-    Symbol oldType = type;
+    Expression oldRange = range;
-    type = newType;
+    range = newRange;
    if (eNotificationRequired())
    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PARAMETER__TYPE, oldType, newType);
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.ASSERTION__RANGE, oldRange, newRange);
      if (msgs == null) msgs = notification; else msgs.add(notification);
    }
    return msgs;
@@ -158,20 +156,20 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
   * @generated
   */
  @Override
-  public void setType(Symbol newType)
+  public void setRange(Expression newRange)
  {
-    if (newType != type)
+    if (newRange != range)
    {
      NotificationChain msgs = null;
-      if (type != null)
+      if (range != null)
-        msgs = ((InternalEObject)type).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PARAMETER__TYPE, null, msgs);
+        msgs = ((InternalEObject)range).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.ASSERTION__RANGE, null, msgs);
-      if (newType != null)
+      if (newRange != null)
-        msgs = ((InternalEObject)newType).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PARAMETER__TYPE, null, msgs);
+        msgs = ((InternalEObject)newRange).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.ASSERTION__RANGE, null, msgs);
-      msgs = basicSetType(newType, msgs);
+      msgs = basicSetRange(newRange, msgs);
      if (msgs != null) msgs.dispatch();
    }
    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PARAMETER__TYPE, newType, newType));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.ASSERTION__RANGE, newRange, newRange));
  }
  /**
@@ -184,10 +182,10 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PARAMETER__VARIABLE:
+      case SolverLanguagePackage.ASSERTION__BODY:
-        return basicSetVariable(null, msgs);
+        return basicSetBody(null, msgs);
-      case SolverLanguagePackage.PARAMETER__TYPE:
+      case SolverLanguagePackage.ASSERTION__RANGE:
-        return basicSetType(null, msgs);
+        return basicSetRange(null, msgs);
    }
    return super.eInverseRemove(otherEnd, featureID, msgs);
  }
@@ -202,10 +200,10 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PARAMETER__VARIABLE:
+      case SolverLanguagePackage.ASSERTION__BODY:
-        return getVariable();
+        return getBody();
-      case SolverLanguagePackage.PARAMETER__TYPE:
+      case SolverLanguagePackage.ASSERTION__RANGE:
-        return getType();
+        return getRange();
    }
    return super.eGet(featureID, resolve, coreType);
  }
@@ -220,11 +218,11 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PARAMETER__VARIABLE:
+      case SolverLanguagePackage.ASSERTION__BODY:
-        setVariable((Variable)newValue);
+        setBody((Expression)newValue);
        return;
-      case SolverLanguagePackage.PARAMETER__TYPE:
+      case SolverLanguagePackage.ASSERTION__RANGE:
-        setType((Symbol)newValue);
+        setRange((Expression)newValue);
        return;
    }
    super.eSet(featureID, newValue);
@@ -240,11 +238,11 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PARAMETER__VARIABLE:
+      case SolverLanguagePackage.ASSERTION__BODY:
-        setVariable((Variable)null);
+        setBody((Expression)null);
        return;
-      case SolverLanguagePackage.PARAMETER__TYPE:
+      case SolverLanguagePackage.ASSERTION__RANGE:
-        setType((Symbol)null);
+        setRange((Expression)null);
        return;
    }
    super.eUnset(featureID);
@@ -260,12 +258,12 @@ public class ParameterImpl extends MinimalEObjectImpl.Container implements Param
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.PARAMETER__VARIABLE:
+      case SolverLanguagePackage.ASSERTION__BODY:
-        return variable != null;
+        return body != null;
-      case SolverLanguagePackage.PARAMETER__TYPE:
+      case SolverLanguagePackage.ASSERTION__RANGE:
-        return type != null;
+        return range != null;
    }
    return super.eIsSet(featureID);
  }
-} //ParameterImpl
+} //AssertionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BasicInterpretationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BasicInterpretationImpl.java
deleted file mode 100644
index aef515f6..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BasicInterpretationImpl.java
+++ /dev/null
@@ -1,318 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import java.util.Collection;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.common.notify.NotificationChain;
-import org.eclipse.emf.common.util.EList;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.InternalEObject;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.util.EObjectContainmentEList;
-import org.eclipse.emf.ecore.util.InternalEList;
-import org.eclipse.viatra.solver.language.solverLanguage.BasicInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.ComplexObject;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Symbol;
-import org.eclipse.viatra.solver.language.solverLanguage.TruthValue;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Basic Interpretation</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BasicInterpretationImpl#getSymbol <em>Symbol</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BasicInterpretationImpl#getObjects <em>Objects</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BasicInterpretationImpl#getValue <em>Value</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class BasicInterpretationImpl extends InterpretationImpl implements BasicInterpretation
-{
-  /**
-   * The cached value of the '{@link #getSymbol() <em>Symbol</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSymbol()
-   * @generated
-   * @ordered
-   */
-  protected Symbol symbol;
-  /**
-   * The cached value of the '{@link #getObjects() <em>Objects</em>}' containment reference list.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getObjects()
-   * @generated
-   * @ordered
-   */
-  protected EList<ComplexObject> objects;
-  /**
-   * The cached value of the '{@link #getValue() <em>Value</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getValue()
-   * @generated
-   * @ordered
-   */
-  protected TruthValue value;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected BasicInterpretationImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.BASIC_INTERPRETATION;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Symbol getSymbol()
-  {
-    return symbol;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSymbol(Symbol newSymbol, NotificationChain msgs)
-  {
-    Symbol oldSymbol = symbol;
-    symbol = newSymbol;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL, oldSymbol, newSymbol);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSymbol(Symbol newSymbol)
-  {
-    if (newSymbol != symbol)
-    {
-      NotificationChain msgs = null;
-      if (symbol != null)
-        msgs = ((InternalEObject)symbol).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL, null, msgs);
-      if (newSymbol != null)
-        msgs = ((InternalEObject)newSymbol).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL, null, msgs);
-      msgs = basicSetSymbol(newSymbol, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL, newSymbol, newSymbol));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public EList<ComplexObject> getObjects()
-  {
-    if (objects == null)
-    {
-      objects = new EObjectContainmentEList<ComplexObject>(ComplexObject.class, this, SolverLanguagePackage.BASIC_INTERPRETATION__OBJECTS);
-    }
-    return objects;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public TruthValue getValue()
-  {
-    return value;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetValue(TruthValue newValue, NotificationChain msgs)
-  {
-    TruthValue oldValue = value;
-    value = newValue;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BASIC_INTERPRETATION__VALUE, oldValue, newValue);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setValue(TruthValue newValue)
-  {
-    if (newValue != value)
-    {
-      NotificationChain msgs = null;
-      if (value != null)
-        msgs = ((InternalEObject)value).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BASIC_INTERPRETATION__VALUE, null, msgs);
-      if (newValue != null)
-        msgs = ((InternalEObject)newValue).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BASIC_INTERPRETATION__VALUE, null, msgs);
-      msgs = basicSetValue(newValue, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BASIC_INTERPRETATION__VALUE, newValue, newValue));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL:
-        return basicSetSymbol(null, msgs);
-      case SolverLanguagePackage.BASIC_INTERPRETATION__OBJECTS:
-        return ((InternalEList<?>)getObjects()).basicRemove(otherEnd, msgs);
-      case SolverLanguagePackage.BASIC_INTERPRETATION__VALUE:
-        return basicSetValue(null, msgs);
-    }
-    return super.eInverseRemove(otherEnd, featureID, msgs);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL:
-        return getSymbol();
-      case SolverLanguagePackage.BASIC_INTERPRETATION__OBJECTS:
-        return getObjects();
-      case SolverLanguagePackage.BASIC_INTERPRETATION__VALUE:
-        return getValue();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @SuppressWarnings("unchecked")
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL:
-        setSymbol((Symbol)newValue);
-        return;
-      case SolverLanguagePackage.BASIC_INTERPRETATION__OBJECTS:
-        getObjects().clear();
-        getObjects().addAll((Collection<? extends ComplexObject>)newValue);
-        return;
-      case SolverLanguagePackage.BASIC_INTERPRETATION__VALUE:
-        setValue((TruthValue)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL:
-        setSymbol((Symbol)null);
-        return;
-      case SolverLanguagePackage.BASIC_INTERPRETATION__OBJECTS:
-        getObjects().clear();
-        return;
-      case SolverLanguagePackage.BASIC_INTERPRETATION__VALUE:
-        setValue((TruthValue)null);
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.BASIC_INTERPRETATION__SYMBOL:
-        return symbol != null;
-      case SolverLanguagePackage.BASIC_INTERPRETATION__OBJECTS:
-        return objects != null && !objects.isEmpty();
-      case SolverLanguagePackage.BASIC_INTERPRETATION__VALUE:
-        return value != null;
-    }
-    return super.eIsSet(featureID);
-  }
-} //BasicInterpretationImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BinaryExpressionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BinaryExpressionImpl.java
new file mode 100644
index 00000000..adc94c4a
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BinaryExpressionImpl.java
@@ -0,0 +1,343 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.BinaryExpression;
+import org.eclipse.viatra.solver.language.solverLanguage.BinaryOperator;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Binary Expression</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BinaryExpressionImpl#getLeft <em>Left</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BinaryExpressionImpl#getOp <em>Op</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BinaryExpressionImpl#getRight <em>Right</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class BinaryExpressionImpl extends ExpressionImpl implements BinaryExpression
+{
+  /**
+   * The cached value of the '{@link #getLeft() <em>Left</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLeft()
+   * @generated
+   * @ordered
+   */
+  protected Expression left;
+  /**
+   * The default value of the '{@link #getOp() <em>Op</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOp()
+   * @generated
+   * @ordered
+   */
+  protected static final BinaryOperator OP_EDEFAULT = BinaryOperator.EQ;
+  /**
+   * The cached value of the '{@link #getOp() <em>Op</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOp()
+   * @generated
+   * @ordered
+   */
+  protected BinaryOperator op = OP_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getRight() <em>Right</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getRight()
+   * @generated
+   * @ordered
+   */
+  protected Expression right;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected BinaryExpressionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.BINARY_EXPRESSION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getLeft()
+  {
+    return left;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetLeft(Expression newLeft, NotificationChain msgs)
+  {
+    Expression oldLeft = left;
+    left = newLeft;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BINARY_EXPRESSION__LEFT, oldLeft, newLeft);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setLeft(Expression newLeft)
+  {
+    if (newLeft != left)
+    {
+      NotificationChain msgs = null;
+      if (left != null)
+        msgs = ((InternalEObject)left).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BINARY_EXPRESSION__LEFT, null, msgs);
+      if (newLeft != null)
+        msgs = ((InternalEObject)newLeft).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BINARY_EXPRESSION__LEFT, null, msgs);
+      msgs = basicSetLeft(newLeft, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BINARY_EXPRESSION__LEFT, newLeft, newLeft));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public BinaryOperator getOp()
+  {
+    return op;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setOp(BinaryOperator newOp)
+  {
+    BinaryOperator oldOp = op;
+    op = newOp == null ? OP_EDEFAULT : newOp;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BINARY_EXPRESSION__OP, oldOp, op));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getRight()
+  {
+    return right;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetRight(Expression newRight, NotificationChain msgs)
+  {
+    Expression oldRight = right;
+    right = newRight;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BINARY_EXPRESSION__RIGHT, oldRight, newRight);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setRight(Expression newRight)
+  {
+    if (newRight != right)
+    {
+      NotificationChain msgs = null;
+      if (right != null)
+        msgs = ((InternalEObject)right).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BINARY_EXPRESSION__RIGHT, null, msgs);
+      if (newRight != null)
+        msgs = ((InternalEObject)newRight).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BINARY_EXPRESSION__RIGHT, null, msgs);
+      msgs = basicSetRight(newRight, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BINARY_EXPRESSION__RIGHT, newRight, newRight));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BINARY_EXPRESSION__LEFT:
+        return basicSetLeft(null, msgs);
+      case SolverLanguagePackage.BINARY_EXPRESSION__RIGHT:
+        return basicSetRight(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BINARY_EXPRESSION__LEFT:
+        return getLeft();
+      case SolverLanguagePackage.BINARY_EXPRESSION__OP:
+        return getOp();
+      case SolverLanguagePackage.BINARY_EXPRESSION__RIGHT:
+        return getRight();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BINARY_EXPRESSION__LEFT:
+        setLeft((Expression)newValue);
+        return;
+      case SolverLanguagePackage.BINARY_EXPRESSION__OP:
+        setOp((BinaryOperator)newValue);
+        return;
+      case SolverLanguagePackage.BINARY_EXPRESSION__RIGHT:
+        setRight((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BINARY_EXPRESSION__LEFT:
+        setLeft((Expression)null);
+        return;
+      case SolverLanguagePackage.BINARY_EXPRESSION__OP:
+        setOp(OP_EDEFAULT);
+        return;
+      case SolverLanguagePackage.BINARY_EXPRESSION__RIGHT:
+        setRight((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BINARY_EXPRESSION__LEFT:
+        return left != null;
+      case SolverLanguagePackage.BINARY_EXPRESSION__OP:
+        return op != OP_EDEFAULT;
+      case SolverLanguagePackage.BINARY_EXPRESSION__RIGHT:
+        return right != null;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (op: ");
+    result.append(op);
+    result.append(')');
+    return result.toString();
+  }
+} //BinaryExpressionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanFalseImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanFalseImpl.java
deleted file mode 100644
index ae78f540..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanFalseImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanFalse;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Boolean False</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class BooleanFalseImpl extends BooleanValueImpl implements BooleanFalse
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected BooleanFalseImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.BOOLEAN_FALSE;
-  }
-} //BooleanFalseImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanTrueImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanTrueImpl.java
deleted file mode 100644
index 4d110ee9..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanTrueImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanTrue;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Boolean True</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class BooleanTrueImpl extends BooleanValueImpl implements BooleanTrue
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected BooleanTrueImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.BOOLEAN_TRUE;
-  }
-} //BooleanTrueImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanValueImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanValueImpl.java
deleted file mode 100644
index b27ab959..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanValueImpl.java
+++ /dev/null
@@ -1,43 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanValue;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Boolean Value</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class BooleanValueImpl extends MinimalEObjectImpl.Container implements BooleanValue
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected BooleanValueImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.BOOLEAN_VALUE;
-  }
-} //BooleanValueImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BoundedMultiplicityImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BoundedMultiplicityImpl.java
new file mode 100644
index 00000000..45a105e0
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BoundedMultiplicityImpl.java
@@ -0,0 +1,237 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.BoundedMultiplicity;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Bounded Multiplicity</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BoundedMultiplicityImpl#getLowerBound <em>Lower Bound</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BoundedMultiplicityImpl#getUpperBound <em>Upper Bound</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class BoundedMultiplicityImpl extends MultiplicityImpl implements BoundedMultiplicity
+{
+  /**
+   * The default value of the '{@link #getLowerBound() <em>Lower Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLowerBound()
+   * @generated
+   * @ordered
+   */
+  protected static final int LOWER_BOUND_EDEFAULT = 0;
+  /**
+   * The cached value of the '{@link #getLowerBound() <em>Lower Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLowerBound()
+   * @generated
+   * @ordered
+   */
+  protected int lowerBound = LOWER_BOUND_EDEFAULT;
+  /**
+   * The default value of the '{@link #getUpperBound() <em>Upper Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getUpperBound()
+   * @generated
+   * @ordered
+   */
+  protected static final int UPPER_BOUND_EDEFAULT = 0;
+  /**
+   * The cached value of the '{@link #getUpperBound() <em>Upper Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getUpperBound()
+   * @generated
+   * @ordered
+   */
+  protected int upperBound = UPPER_BOUND_EDEFAULT;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected BoundedMultiplicityImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.BOUNDED_MULTIPLICITY;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public int getLowerBound()
+  {
+    return lowerBound;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setLowerBound(int newLowerBound)
+  {
+    int oldLowerBound = lowerBound;
+    lowerBound = newLowerBound;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BOUNDED_MULTIPLICITY__LOWER_BOUND, oldLowerBound, lowerBound));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public int getUpperBound()
+  {
+    return upperBound;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setUpperBound(int newUpperBound)
+  {
+    int oldUpperBound = upperBound;
+    upperBound = newUpperBound;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BOUNDED_MULTIPLICITY__UPPER_BOUND, oldUpperBound, upperBound));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY__LOWER_BOUND:
+        return getLowerBound();
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY__UPPER_BOUND:
+        return getUpperBound();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY__LOWER_BOUND:
+        setLowerBound((Integer)newValue);
+        return;
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY__UPPER_BOUND:
+        setUpperBound((Integer)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY__LOWER_BOUND:
+        setLowerBound(LOWER_BOUND_EDEFAULT);
+        return;
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY__UPPER_BOUND:
+        setUpperBound(UPPER_BOUND_EDEFAULT);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY__LOWER_BOUND:
+        return lowerBound != LOWER_BOUND_EDEFAULT;
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY__UPPER_BOUND:
+        return upperBound != UPPER_BOUND_EDEFAULT;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (lowerBound: ");
+    result.append(lowerBound);
+    result.append(", upperBound: ");
+    result.append(upperBound);
+    result.append(')');
+    return result.toString();
+  }
+} //BoundedMultiplicityImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BoundedScopeDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BoundedScopeDefinitionImpl.java
new file mode 100644
index 00000000..36bf4f96
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BoundedScopeDefinitionImpl.java
@@ -0,0 +1,237 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.BoundedScopeDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Bounded Scope Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BoundedScopeDefinitionImpl#getLowerBound <em>Lower Bound</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BoundedScopeDefinitionImpl#getUpperBound <em>Upper Bound</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class BoundedScopeDefinitionImpl extends ScopeDefinitionImpl implements BoundedScopeDefinition
+{
+  /**
+   * The default value of the '{@link #getLowerBound() <em>Lower Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLowerBound()
+   * @generated
+   * @ordered
+   */
+  protected static final int LOWER_BOUND_EDEFAULT = 0;
+  /**
+   * The cached value of the '{@link #getLowerBound() <em>Lower Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLowerBound()
+   * @generated
+   * @ordered
+   */
+  protected int lowerBound = LOWER_BOUND_EDEFAULT;
+  /**
+   * The default value of the '{@link #getUpperBound() <em>Upper Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getUpperBound()
+   * @generated
+   * @ordered
+   */
+  protected static final int UPPER_BOUND_EDEFAULT = 0;
+  /**
+   * The cached value of the '{@link #getUpperBound() <em>Upper Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getUpperBound()
+   * @generated
+   * @ordered
+   */
+  protected int upperBound = UPPER_BOUND_EDEFAULT;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected BoundedScopeDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.BOUNDED_SCOPE_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public int getLowerBound()
+  {
+    return lowerBound;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setLowerBound(int newLowerBound)
+  {
+    int oldLowerBound = lowerBound;
+    lowerBound = newLowerBound;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__LOWER_BOUND, oldLowerBound, lowerBound));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public int getUpperBound()
+  {
+    return upperBound;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setUpperBound(int newUpperBound)
+  {
+    int oldUpperBound = upperBound;
+    upperBound = newUpperBound;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__UPPER_BOUND, oldUpperBound, upperBound));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__LOWER_BOUND:
+        return getLowerBound();
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__UPPER_BOUND:
+        return getUpperBound();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__LOWER_BOUND:
+        setLowerBound((Integer)newValue);
+        return;
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__UPPER_BOUND:
+        setUpperBound((Integer)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__LOWER_BOUND:
+        setLowerBound(LOWER_BOUND_EDEFAULT);
+        return;
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__UPPER_BOUND:
+        setUpperBound(UPPER_BOUND_EDEFAULT);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__LOWER_BOUND:
+        return lowerBound != LOWER_BOUND_EDEFAULT;
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION__UPPER_BOUND:
+        return upperBound != UPPER_BOUND_EDEFAULT;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (lowerBound: ");
+    result.append(lowerBound);
+    result.append(", upperBound: ");
+    result.append(upperBound);
+    result.append(')');
+    return result.toString();
+  }
+} //BoundedScopeDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CDInterpretationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CDInterpretationImpl.java
deleted file mode 100644
index b23bbba5..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CDInterpretationImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.CDInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>CD Interpretation</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class CDInterpretationImpl extends InterpretationImpl implements CDInterpretation
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected CDInterpretationImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.CD_INTERPRETATION;
-  }
-} //CDInterpretationImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CallImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CallImpl.java
new file mode 100644
index 00000000..fde31be5
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CallImpl.java
@@ -0,0 +1,401 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.ArgumentList;
+import org.eclipse.viatra.solver.language.solverLanguage.Call;
+import org.eclipse.viatra.solver.language.solverLanguage.Reference;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Call</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.CallImpl#getFunctor <em>Functor</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.CallImpl#getArgumentList <em>Argument List</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.CallImpl#isTransitiveClosure <em>Transitive Closure</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.CallImpl#isReflexiveTransitiveClosure <em>Reflexive Transitive Closure</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class CallImpl extends ExpressionImpl implements Call
+{
+  /**
+   * The cached value of the '{@link #getFunctor() <em>Functor</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getFunctor()
+   * @generated
+   * @ordered
+   */
+  protected Reference functor;
+  /**
+   * The cached value of the '{@link #getArgumentList() <em>Argument List</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getArgumentList()
+   * @generated
+   * @ordered
+   */
+  protected ArgumentList argumentList;
+  /**
+   * The default value of the '{@link #isTransitiveClosure() <em>Transitive Closure</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isTransitiveClosure()
+   * @generated
+   * @ordered
+   */
+  protected static final boolean TRANSITIVE_CLOSURE_EDEFAULT = false;
+  /**
+   * The cached value of the '{@link #isTransitiveClosure() <em>Transitive Closure</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isTransitiveClosure()
+   * @generated
+   * @ordered
+   */
+  protected boolean transitiveClosure = TRANSITIVE_CLOSURE_EDEFAULT;
+  /**
+   * The default value of the '{@link #isReflexiveTransitiveClosure() <em>Reflexive Transitive Closure</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isReflexiveTransitiveClosure()
+   * @generated
+   * @ordered
+   */
+  protected static final boolean REFLEXIVE_TRANSITIVE_CLOSURE_EDEFAULT = false;
+  /**
+   * The cached value of the '{@link #isReflexiveTransitiveClosure() <em>Reflexive Transitive Closure</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isReflexiveTransitiveClosure()
+   * @generated
+   * @ordered
+   */
+  protected boolean reflexiveTransitiveClosure = REFLEXIVE_TRANSITIVE_CLOSURE_EDEFAULT;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected CallImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.CALL;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Reference getFunctor()
+  {
+    return functor;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetFunctor(Reference newFunctor, NotificationChain msgs)
+  {
+    Reference oldFunctor = functor;
+    functor = newFunctor;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CALL__FUNCTOR, oldFunctor, newFunctor);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setFunctor(Reference newFunctor)
+  {
+    if (newFunctor != functor)
+    {
+      NotificationChain msgs = null;
+      if (functor != null)
+        msgs = ((InternalEObject)functor).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CALL__FUNCTOR, null, msgs);
+      if (newFunctor != null)
+        msgs = ((InternalEObject)newFunctor).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CALL__FUNCTOR, null, msgs);
+      msgs = basicSetFunctor(newFunctor, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CALL__FUNCTOR, newFunctor, newFunctor));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public ArgumentList getArgumentList()
+  {
+    return argumentList;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetArgumentList(ArgumentList newArgumentList, NotificationChain msgs)
+  {
+    ArgumentList oldArgumentList = argumentList;
+    argumentList = newArgumentList;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CALL__ARGUMENT_LIST, oldArgumentList, newArgumentList);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setArgumentList(ArgumentList newArgumentList)
+  {
+    if (newArgumentList != argumentList)
+    {
+      NotificationChain msgs = null;
+      if (argumentList != null)
+        msgs = ((InternalEObject)argumentList).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CALL__ARGUMENT_LIST, null, msgs);
+      if (newArgumentList != null)
+        msgs = ((InternalEObject)newArgumentList).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CALL__ARGUMENT_LIST, null, msgs);
+      msgs = basicSetArgumentList(newArgumentList, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CALL__ARGUMENT_LIST, newArgumentList, newArgumentList));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean isTransitiveClosure()
+  {
+    return transitiveClosure;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setTransitiveClosure(boolean newTransitiveClosure)
+  {
+    boolean oldTransitiveClosure = transitiveClosure;
+    transitiveClosure = newTransitiveClosure;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CALL__TRANSITIVE_CLOSURE, oldTransitiveClosure, transitiveClosure));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean isReflexiveTransitiveClosure()
+  {
+    return reflexiveTransitiveClosure;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setReflexiveTransitiveClosure(boolean newReflexiveTransitiveClosure)
+  {
+    boolean oldReflexiveTransitiveClosure = reflexiveTransitiveClosure;
+    reflexiveTransitiveClosure = newReflexiveTransitiveClosure;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CALL__REFLEXIVE_TRANSITIVE_CLOSURE, oldReflexiveTransitiveClosure, reflexiveTransitiveClosure));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CALL__FUNCTOR:
+        return basicSetFunctor(null, msgs);
+      case SolverLanguagePackage.CALL__ARGUMENT_LIST:
+        return basicSetArgumentList(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CALL__FUNCTOR:
+        return getFunctor();
+      case SolverLanguagePackage.CALL__ARGUMENT_LIST:
+        return getArgumentList();
+      case SolverLanguagePackage.CALL__TRANSITIVE_CLOSURE:
+        return isTransitiveClosure();
+      case SolverLanguagePackage.CALL__REFLEXIVE_TRANSITIVE_CLOSURE:
+        return isReflexiveTransitiveClosure();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CALL__FUNCTOR:
+        setFunctor((Reference)newValue);
+        return;
+      case SolverLanguagePackage.CALL__ARGUMENT_LIST:
+        setArgumentList((ArgumentList)newValue);
+        return;
+      case SolverLanguagePackage.CALL__TRANSITIVE_CLOSURE:
+        setTransitiveClosure((Boolean)newValue);
+        return;
+      case SolverLanguagePackage.CALL__REFLEXIVE_TRANSITIVE_CLOSURE:
+        setReflexiveTransitiveClosure((Boolean)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CALL__FUNCTOR:
+        setFunctor((Reference)null);
+        return;
+      case SolverLanguagePackage.CALL__ARGUMENT_LIST:
+        setArgumentList((ArgumentList)null);
+        return;
+      case SolverLanguagePackage.CALL__TRANSITIVE_CLOSURE:
+        setTransitiveClosure(TRANSITIVE_CLOSURE_EDEFAULT);
+        return;
+      case SolverLanguagePackage.CALL__REFLEXIVE_TRANSITIVE_CLOSURE:
+        setReflexiveTransitiveClosure(REFLEXIVE_TRANSITIVE_CLOSURE_EDEFAULT);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CALL__FUNCTOR:
+        return functor != null;
+      case SolverLanguagePackage.CALL__ARGUMENT_LIST:
+        return argumentList != null;
+      case SolverLanguagePackage.CALL__TRANSITIVE_CLOSURE:
+        return transitiveClosure != TRANSITIVE_CLOSURE_EDEFAULT;
+      case SolverLanguagePackage.CALL__REFLEXIVE_TRANSITIVE_CLOSURE:
+        return reflexiveTransitiveClosure != REFLEXIVE_TRANSITIVE_CLOSURE_EDEFAULT;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (transitiveClosure: ");
+    result.append(transitiveClosure);
+    result.append(", reflexiveTransitiveClosure: ");
+    result.append(reflexiveTransitiveClosure);
+    result.append(')');
+    return result.toString();
+  }
+} //CallImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CaseImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CaseImpl.java
new file mode 100644
index 00000000..47245831
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CaseImpl.java
@@ -0,0 +1,269 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Case;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Case</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.CaseImpl#getCondition <em>Condition</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.CaseImpl#getBody <em>Body</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class CaseImpl extends ExpressionImpl implements Case
+{
+  /**
+   * The cached value of the '{@link #getCondition() <em>Condition</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getCondition()
+   * @generated
+   * @ordered
+   */
+  protected Expression condition;
+  /**
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getBody()
+   * @generated
+   * @ordered
+   */
+  protected Expression body;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected CaseImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.CASE;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getCondition()
+  {
+    return condition;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetCondition(Expression newCondition, NotificationChain msgs)
+  {
+    Expression oldCondition = condition;
+    condition = newCondition;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CASE__CONDITION, oldCondition, newCondition);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setCondition(Expression newCondition)
+  {
+    if (newCondition != condition)
+    {
+      NotificationChain msgs = null;
+      if (condition != null)
+        msgs = ((InternalEObject)condition).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CASE__CONDITION, null, msgs);
+      if (newCondition != null)
+        msgs = ((InternalEObject)newCondition).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CASE__CONDITION, null, msgs);
+      msgs = basicSetCondition(newCondition, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CASE__CONDITION, newCondition, newCondition));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getBody()
+  {
+    return body;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
+  {
+    Expression oldBody = body;
+    body = newBody;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CASE__BODY, oldBody, newBody);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setBody(Expression newBody)
+  {
+    if (newBody != body)
+    {
+      NotificationChain msgs = null;
+      if (body != null)
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CASE__BODY, null, msgs);
+      if (newBody != null)
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CASE__BODY, null, msgs);
+      msgs = basicSetBody(newBody, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CASE__BODY, newBody, newBody));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CASE__CONDITION:
+        return basicSetCondition(null, msgs);
+      case SolverLanguagePackage.CASE__BODY:
+        return basicSetBody(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CASE__CONDITION:
+        return getCondition();
+      case SolverLanguagePackage.CASE__BODY:
+        return getBody();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CASE__CONDITION:
+        setCondition((Expression)newValue);
+        return;
+      case SolverLanguagePackage.CASE__BODY:
+        setBody((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CASE__CONDITION:
+        setCondition((Expression)null);
+        return;
+      case SolverLanguagePackage.CASE__BODY:
+        setBody((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CASE__CONDITION:
+        return condition != null;
+      case SolverLanguagePackage.CASE__BODY:
+        return body != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //CaseImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ClassInterpretationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ClassInterpretationImpl.java
deleted file mode 100644
index effc5970..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ClassInterpretationImpl.java
+++ /dev/null
@@ -1,356 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import java.util.Collection;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.common.notify.NotificationChain;
-import org.eclipse.emf.common.util.EList;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.InternalEObject;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.util.EObjectContainmentEList;
-import org.eclipse.emf.ecore.util.InternalEList;
-import org.eclipse.viatra.solver.language.solverLanguage.ClassInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.FieldRelationInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Class Interpretation</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ClassInterpretationImpl#isAbstract <em>Abstract</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ClassInterpretationImpl#getSymbol <em>Symbol</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ClassInterpretationImpl#getSupertypes <em>Supertypes</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ClassInterpretationImpl#getFielt <em>Fielt</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class ClassInterpretationImpl extends CDInterpretationImpl implements ClassInterpretation
-{
-  /**
-   * The default value of the '{@link #isAbstract() <em>Abstract</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isAbstract()
-   * @generated
-   * @ordered
-   */
-  protected static final boolean ABSTRACT_EDEFAULT = false;
-  /**
-   * The cached value of the '{@link #isAbstract() <em>Abstract</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isAbstract()
-   * @generated
-   * @ordered
-   */
-  protected boolean abstract_ = ABSTRACT_EDEFAULT;
-  /**
-   * The cached value of the '{@link #getSymbol() <em>Symbol</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSymbol()
-   * @generated
-   * @ordered
-   */
-  protected ModelSymbol symbol;
-  /**
-   * The cached value of the '{@link #getSupertypes() <em>Supertypes</em>}' containment reference list.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSupertypes()
-   * @generated
-   * @ordered
-   */
-  protected EList<ModelSymbol> supertypes;
-  /**
-   * The cached value of the '{@link #getFielt() <em>Fielt</em>}' containment reference list.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getFielt()
-   * @generated
-   * @ordered
-   */
-  protected EList<FieldRelationInterpretation> fielt;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected ClassInterpretationImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.CLASS_INTERPRETATION;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean isAbstract()
-  {
-    return abstract_;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setAbstract(boolean newAbstract)
-  {
-    boolean oldAbstract = abstract_;
-    abstract_ = newAbstract;
-    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CLASS_INTERPRETATION__ABSTRACT, oldAbstract, abstract_));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public ModelSymbol getSymbol()
-  {
-    return symbol;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSymbol(ModelSymbol newSymbol, NotificationChain msgs)
-  {
-    ModelSymbol oldSymbol = symbol;
-    symbol = newSymbol;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL, oldSymbol, newSymbol);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSymbol(ModelSymbol newSymbol)
-  {
-    if (newSymbol != symbol)
-    {
-      NotificationChain msgs = null;
-      if (symbol != null)
-        msgs = ((InternalEObject)symbol).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL, null, msgs);
-      if (newSymbol != null)
-        msgs = ((InternalEObject)newSymbol).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL, null, msgs);
-      msgs = basicSetSymbol(newSymbol, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL, newSymbol, newSymbol));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public EList<ModelSymbol> getSupertypes()
-  {
-    if (supertypes == null)
-    {
-      supertypes = new EObjectContainmentEList<ModelSymbol>(ModelSymbol.class, this, SolverLanguagePackage.CLASS_INTERPRETATION__SUPERTYPES);
-    }
-    return supertypes;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public EList<FieldRelationInterpretation> getFielt()
-  {
-    if (fielt == null)
-    {
-      fielt = new EObjectContainmentEList<FieldRelationInterpretation>(FieldRelationInterpretation.class, this, SolverLanguagePackage.CLASS_INTERPRETATION__FIELT);
-    }
-    return fielt;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL:
-        return basicSetSymbol(null, msgs);
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SUPERTYPES:
-        return ((InternalEList<?>)getSupertypes()).basicRemove(otherEnd, msgs);
-      case SolverLanguagePackage.CLASS_INTERPRETATION__FIELT:
-        return ((InternalEList<?>)getFielt()).basicRemove(otherEnd, msgs);
-    }
-    return super.eInverseRemove(otherEnd, featureID, msgs);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CLASS_INTERPRETATION__ABSTRACT:
-        return isAbstract();
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL:
-        return getSymbol();
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SUPERTYPES:
-        return getSupertypes();
-      case SolverLanguagePackage.CLASS_INTERPRETATION__FIELT:
-        return getFielt();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @SuppressWarnings("unchecked")
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CLASS_INTERPRETATION__ABSTRACT:
-        setAbstract((Boolean)newValue);
-        return;
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL:
-        setSymbol((ModelSymbol)newValue);
-        return;
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SUPERTYPES:
-        getSupertypes().clear();
-        getSupertypes().addAll((Collection<? extends ModelSymbol>)newValue);
-        return;
-      case SolverLanguagePackage.CLASS_INTERPRETATION__FIELT:
-        getFielt().clear();
-        getFielt().addAll((Collection<? extends FieldRelationInterpretation>)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CLASS_INTERPRETATION__ABSTRACT:
-        setAbstract(ABSTRACT_EDEFAULT);
-        return;
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL:
-        setSymbol((ModelSymbol)null);
-        return;
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SUPERTYPES:
-        getSupertypes().clear();
-        return;
-      case SolverLanguagePackage.CLASS_INTERPRETATION__FIELT:
-        getFielt().clear();
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CLASS_INTERPRETATION__ABSTRACT:
-        return abstract_ != ABSTRACT_EDEFAULT;
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SYMBOL:
-        return symbol != null;
-      case SolverLanguagePackage.CLASS_INTERPRETATION__SUPERTYPES:
-        return supertypes != null && !supertypes.isEmpty();
-      case SolverLanguagePackage.CLASS_INTERPRETATION__FIELT:
-        return fielt != null && !fielt.isEmpty();
-    }
-    return super.eIsSet(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public String toString()
-  {
-    if (eIsProxy()) return super.toString();
-    StringBuilder result = new StringBuilder(super.toString());
-    result.append(" (abstract: ");
-    result.append(abstract_);
-    result.append(')');
-    return result.toString();
-  }
-} //ClassInterpretationImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ComparisonImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ComparisonImpl.java
new file mode 100644
index 00000000..9e62d7ef
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ComparisonImpl.java
@@ -0,0 +1,343 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.BinaryOperator;
+import org.eclipse.viatra.solver.language.solverLanguage.Comparison;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Comparison</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ComparisonImpl#getLeft <em>Left</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ComparisonImpl#getOp <em>Op</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ComparisonImpl#getRight <em>Right</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class ComparisonImpl extends ExpressionImpl implements Comparison
+{
+  /**
+   * The cached value of the '{@link #getLeft() <em>Left</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLeft()
+   * @generated
+   * @ordered
+   */
+  protected Expression left;
+  /**
+   * The default value of the '{@link #getOp() <em>Op</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOp()
+   * @generated
+   * @ordered
+   */
+  protected static final BinaryOperator OP_EDEFAULT = BinaryOperator.EQ;
+  /**
+   * The cached value of the '{@link #getOp() <em>Op</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOp()
+   * @generated
+   * @ordered
+   */
+  protected BinaryOperator op = OP_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getRight() <em>Right</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getRight()
+   * @generated
+   * @ordered
+   */
+  protected Expression right;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected ComparisonImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.COMPARISON;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getLeft()
+  {
+    return left;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetLeft(Expression newLeft, NotificationChain msgs)
+  {
+    Expression oldLeft = left;
+    left = newLeft;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.COMPARISON__LEFT, oldLeft, newLeft);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setLeft(Expression newLeft)
+  {
+    if (newLeft != left)
+    {
+      NotificationChain msgs = null;
+      if (left != null)
+        msgs = ((InternalEObject)left).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.COMPARISON__LEFT, null, msgs);
+      if (newLeft != null)
+        msgs = ((InternalEObject)newLeft).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.COMPARISON__LEFT, null, msgs);
+      msgs = basicSetLeft(newLeft, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.COMPARISON__LEFT, newLeft, newLeft));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public BinaryOperator getOp()
+  {
+    return op;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setOp(BinaryOperator newOp)
+  {
+    BinaryOperator oldOp = op;
+    op = newOp == null ? OP_EDEFAULT : newOp;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.COMPARISON__OP, oldOp, op));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getRight()
+  {
+    return right;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetRight(Expression newRight, NotificationChain msgs)
+  {
+    Expression oldRight = right;
+    right = newRight;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.COMPARISON__RIGHT, oldRight, newRight);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setRight(Expression newRight)
+  {
+    if (newRight != right)
+    {
+      NotificationChain msgs = null;
+      if (right != null)
+        msgs = ((InternalEObject)right).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.COMPARISON__RIGHT, null, msgs);
+      if (newRight != null)
+        msgs = ((InternalEObject)newRight).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.COMPARISON__RIGHT, null, msgs);
+      msgs = basicSetRight(newRight, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.COMPARISON__RIGHT, newRight, newRight));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.COMPARISON__LEFT:
+        return basicSetLeft(null, msgs);
+      case SolverLanguagePackage.COMPARISON__RIGHT:
+        return basicSetRight(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.COMPARISON__LEFT:
+        return getLeft();
+      case SolverLanguagePackage.COMPARISON__OP:
+        return getOp();
+      case SolverLanguagePackage.COMPARISON__RIGHT:
+        return getRight();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.COMPARISON__LEFT:
+        setLeft((Expression)newValue);
+        return;
+      case SolverLanguagePackage.COMPARISON__OP:
+        setOp((BinaryOperator)newValue);
+        return;
+      case SolverLanguagePackage.COMPARISON__RIGHT:
+        setRight((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.COMPARISON__LEFT:
+        setLeft((Expression)null);
+        return;
+      case SolverLanguagePackage.COMPARISON__OP:
+        setOp(OP_EDEFAULT);
+        return;
+      case SolverLanguagePackage.COMPARISON__RIGHT:
+        setRight((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.COMPARISON__LEFT:
+        return left != null;
+      case SolverLanguagePackage.COMPARISON__OP:
+        return op != OP_EDEFAULT;
+      case SolverLanguagePackage.COMPARISON__RIGHT:
+        return right != null;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (op: ");
+    result.append(op);
+    result.append(')');
+    return result.toString();
+  }
+} //ComparisonImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ComplexObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ComplexObjectImpl.java
deleted file mode 100644
index 09ad8a6d..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ComplexObjectImpl.java
+++ /dev/null
@@ -1,43 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.ComplexObject;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Complex Object</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class ComplexObjectImpl extends MinimalEObjectImpl.Container implements ComplexObject
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected ComplexObjectImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.COMPLEX_OBJECT;
-  }
-} //ComplexObjectImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ConjunctionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ConjunctionImpl.java
new file mode 100644
index 00000000..6a1e995a
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ConjunctionImpl.java
@@ -0,0 +1,167 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import java.util.Collection;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.common.util.EList;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.util.EObjectContainmentEList;
+import org.eclipse.emf.ecore.util.InternalEList;
+import org.eclipse.viatra.solver.language.solverLanguage.Conjunction;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Conjunction</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ConjunctionImpl#getChildren <em>Children</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class ConjunctionImpl extends ExpressionImpl implements Conjunction
+{
+  /**
+   * The cached value of the '{@link #getChildren() <em>Children</em>}' containment reference list.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getChildren()
+   * @generated
+   * @ordered
+   */
+  protected EList<Expression> children;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected ConjunctionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.CONJUNCTION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EList<Expression> getChildren()
+  {
+    if (children == null)
+    {
+      children = new EObjectContainmentEList<Expression>(Expression.class, this, SolverLanguagePackage.CONJUNCTION__CHILDREN);
+    }
+    return children;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CONJUNCTION__CHILDREN:
+        return ((InternalEList<?>)getChildren()).basicRemove(otherEnd, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CONJUNCTION__CHILDREN:
+        return getChildren();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @SuppressWarnings("unchecked")
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CONJUNCTION__CHILDREN:
+        getChildren().clear();
+        getChildren().addAll((Collection<? extends Expression>)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CONJUNCTION__CHILDREN:
+        getChildren().clear();
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.CONJUNCTION__CHILDREN:
+        return children != null && !children.isEmpty();
+    }
+    return super.eIsSet(featureID);
+  }
+} //ConjunctionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ConstraintImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ConstraintImpl.java
deleted file mode 100644
index 2f990fee..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ConstraintImpl.java
+++ /dev/null
@@ -1,393 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import java.util.Collection;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.common.notify.NotificationChain;
-import org.eclipse.emf.common.util.EList;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.InternalEObject;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.emf.ecore.util.EObjectContainmentEList;
-import org.eclipse.emf.ecore.util.InternalEList;
-import org.eclipse.viatra.solver.language.solverLanguage.ClosureType;
-import org.eclipse.viatra.solver.language.solverLanguage.Constraint;
-import org.eclipse.viatra.solver.language.solverLanguage.Literal;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.Polarity;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Constraint</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ConstraintImpl#getPolarity <em>Polarity</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ConstraintImpl#getSymbol <em>Symbol</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ConstraintImpl#getParams <em>Params</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ConstraintImpl#getClosureType <em>Closure Type</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class ConstraintImpl extends MinimalEObjectImpl.Container implements Constraint
-{
-  /**
-   * The cached value of the '{@link #getPolarity() <em>Polarity</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getPolarity()
-   * @generated
-   * @ordered
-   */
-  protected Polarity polarity;
-  /**
-   * The cached value of the '{@link #getSymbol() <em>Symbol</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSymbol()
-   * @generated
-   * @ordered
-   */
-  protected ModelSymbol symbol;
-  /**
-   * The cached value of the '{@link #getParams() <em>Params</em>}' containment reference list.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getParams()
-   * @generated
-   * @ordered
-   */
-  protected EList<Literal> params;
-  /**
-   * The cached value of the '{@link #getClosureType() <em>Closure Type</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getClosureType()
-   * @generated
-   * @ordered
-   */
-  protected ClosureType closureType;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected ConstraintImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.CONSTRAINT;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Polarity getPolarity()
-  {
-    return polarity;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetPolarity(Polarity newPolarity, NotificationChain msgs)
-  {
-    Polarity oldPolarity = polarity;
-    polarity = newPolarity;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CONSTRAINT__POLARITY, oldPolarity, newPolarity);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setPolarity(Polarity newPolarity)
-  {
-    if (newPolarity != polarity)
-    {
-      NotificationChain msgs = null;
-      if (polarity != null)
-        msgs = ((InternalEObject)polarity).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CONSTRAINT__POLARITY, null, msgs);
-      if (newPolarity != null)
-        msgs = ((InternalEObject)newPolarity).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CONSTRAINT__POLARITY, null, msgs);
-      msgs = basicSetPolarity(newPolarity, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CONSTRAINT__POLARITY, newPolarity, newPolarity));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public ModelSymbol getSymbol()
-  {
-    return symbol;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSymbol(ModelSymbol newSymbol, NotificationChain msgs)
-  {
-    ModelSymbol oldSymbol = symbol;
-    symbol = newSymbol;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CONSTRAINT__SYMBOL, oldSymbol, newSymbol);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSymbol(ModelSymbol newSymbol)
-  {
-    if (newSymbol != symbol)
-    {
-      NotificationChain msgs = null;
-      if (symbol != null)
-        msgs = ((InternalEObject)symbol).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CONSTRAINT__SYMBOL, null, msgs);
-      if (newSymbol != null)
-        msgs = ((InternalEObject)newSymbol).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CONSTRAINT__SYMBOL, null, msgs);
-      msgs = basicSetSymbol(newSymbol, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CONSTRAINT__SYMBOL, newSymbol, newSymbol));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public EList<Literal> getParams()
-  {
-    if (params == null)
-    {
-      params = new EObjectContainmentEList<Literal>(Literal.class, this, SolverLanguagePackage.CONSTRAINT__PARAMS);
-    }
-    return params;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public ClosureType getClosureType()
-  {
-    return closureType;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetClosureType(ClosureType newClosureType, NotificationChain msgs)
-  {
-    ClosureType oldClosureType = closureType;
-    closureType = newClosureType;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE, oldClosureType, newClosureType);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setClosureType(ClosureType newClosureType)
-  {
-    if (newClosureType != closureType)
-    {
-      NotificationChain msgs = null;
-      if (closureType != null)
-        msgs = ((InternalEObject)closureType).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE, null, msgs);
-      if (newClosureType != null)
-        msgs = ((InternalEObject)newClosureType).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE, null, msgs);
-      msgs = basicSetClosureType(newClosureType, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE, newClosureType, newClosureType));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CONSTRAINT__POLARITY:
-        return basicSetPolarity(null, msgs);
-      case SolverLanguagePackage.CONSTRAINT__SYMBOL:
-        return basicSetSymbol(null, msgs);
-      case SolverLanguagePackage.CONSTRAINT__PARAMS:
-        return ((InternalEList<?>)getParams()).basicRemove(otherEnd, msgs);
-      case SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE:
-        return basicSetClosureType(null, msgs);
-    }
-    return super.eInverseRemove(otherEnd, featureID, msgs);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CONSTRAINT__POLARITY:
-        return getPolarity();
-      case SolverLanguagePackage.CONSTRAINT__SYMBOL:
-        return getSymbol();
-      case SolverLanguagePackage.CONSTRAINT__PARAMS:
-        return getParams();
-      case SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE:
-        return getClosureType();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @SuppressWarnings("unchecked")
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CONSTRAINT__POLARITY:
-        setPolarity((Polarity)newValue);
-        return;
-      case SolverLanguagePackage.CONSTRAINT__SYMBOL:
-        setSymbol((ModelSymbol)newValue);
-        return;
-      case SolverLanguagePackage.CONSTRAINT__PARAMS:
-        getParams().clear();
-        getParams().addAll((Collection<? extends Literal>)newValue);
-        return;
-      case SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE:
-        setClosureType((ClosureType)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CONSTRAINT__POLARITY:
-        setPolarity((Polarity)null);
-        return;
-      case SolverLanguagePackage.CONSTRAINT__SYMBOL:
-        setSymbol((ModelSymbol)null);
-        return;
-      case SolverLanguagePackage.CONSTRAINT__PARAMS:
-        getParams().clear();
-        return;
-      case SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE:
-        setClosureType((ClosureType)null);
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.CONSTRAINT__POLARITY:
-        return polarity != null;
-      case SolverLanguagePackage.CONSTRAINT__SYMBOL:
-        return symbol != null;
-      case SolverLanguagePackage.CONSTRAINT__PARAMS:
-        return params != null && !params.isEmpty();
-      case SolverLanguagePackage.CONSTRAINT__CLOSURE_TYPE:
-        return closureType != null;
-    }
-    return super.eIsSet(featureID);
-  }
-} //ConstraintImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AllInstancesImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CountImpl.java
index 5da3bf30..1609245f 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AllInstancesImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/CountImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -11,41 +11,41 @@ import org.eclipse.emf.ecore.InternalEObject;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.AllInstances;
+import org.eclipse.viatra.solver.language.solverLanguage.Count;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Symbol;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>All Instances</b></em>'.
+ * An implementation of the model object '<em><b>Count</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.AllInstancesImpl#getSymbol <em>Symbol</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.CountImpl#getBody <em>Body</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
+public class CountImpl extends ExpressionImpl implements Count
 {
  /**
-   * The cached value of the '{@link #getSymbol() <em>Symbol</em>}' containment reference.
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getSymbol()
+   * @see #getBody()
   * @generated
   * @ordered
   */
-  protected Symbol symbol;
+  protected Expression body;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected AllInstancesImpl()
+  protected CountImpl()
  {
    super();
  }
@@ -58,7 +58,7 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.ALL_INSTANCES;
+    return SolverLanguagePackage.Literals.COUNT;
  }
  /**
@@ -67,9 +67,9 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
   * @generated
   */
  @Override
-  public Symbol getSymbol()
+  public Expression getBody()
  {
-    return symbol;
+    return body;
  }
  /**
@@ -77,13 +77,13 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
   * <!-- end-user-doc -->
   * @generated
   */
-  public NotificationChain basicSetSymbol(Symbol newSymbol, NotificationChain msgs)
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
  {
-    Symbol oldSymbol = symbol;
+    Expression oldBody = body;
-    symbol = newSymbol;
+    body = newBody;
    if (eNotificationRequired())
    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.ALL_INSTANCES__SYMBOL, oldSymbol, newSymbol);
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.COUNT__BODY, oldBody, newBody);
      if (msgs == null) msgs = notification; else msgs.add(notification);
    }
    return msgs;
@@ -95,20 +95,20 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
   * @generated
   */
  @Override
-  public void setSymbol(Symbol newSymbol)
+  public void setBody(Expression newBody)
  {
-    if (newSymbol != symbol)
+    if (newBody != body)
    {
      NotificationChain msgs = null;
-      if (symbol != null)
+      if (body != null)
-        msgs = ((InternalEObject)symbol).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.ALL_INSTANCES__SYMBOL, null, msgs);
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.COUNT__BODY, null, msgs);
-      if (newSymbol != null)
+      if (newBody != null)
-        msgs = ((InternalEObject)newSymbol).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.ALL_INSTANCES__SYMBOL, null, msgs);
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.COUNT__BODY, null, msgs);
-      msgs = basicSetSymbol(newSymbol, msgs);
+      msgs = basicSetBody(newBody, msgs);
      if (msgs != null) msgs.dispatch();
    }
    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.ALL_INSTANCES__SYMBOL, newSymbol, newSymbol));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.COUNT__BODY, newBody, newBody));
  }
  /**
@@ -121,8 +121,8 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.ALL_INSTANCES__SYMBOL:
+      case SolverLanguagePackage.COUNT__BODY:
-        return basicSetSymbol(null, msgs);
+        return basicSetBody(null, msgs);
    }
    return super.eInverseRemove(otherEnd, featureID, msgs);
  }
@@ -137,8 +137,8 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.ALL_INSTANCES__SYMBOL:
+      case SolverLanguagePackage.COUNT__BODY:
-        return getSymbol();
+        return getBody();
    }
    return super.eGet(featureID, resolve, coreType);
  }
@@ -153,8 +153,8 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.ALL_INSTANCES__SYMBOL:
+      case SolverLanguagePackage.COUNT__BODY:
-        setSymbol((Symbol)newValue);
+        setBody((Expression)newValue);
        return;
    }
    super.eSet(featureID, newValue);
@@ -170,8 +170,8 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.ALL_INSTANCES__SYMBOL:
+      case SolverLanguagePackage.COUNT__BODY:
-        setSymbol((Symbol)null);
+        setBody((Expression)null);
        return;
    }
    super.eUnset(featureID);
@@ -187,10 +187,10 @@ public class AllInstancesImpl extends ComplexObjectImpl implements AllInstances
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.ALL_INSTANCES__SYMBOL:
+      case SolverLanguagePackage.COUNT__BODY:
-        return symbol != null;
+        return body != null;
    }
    return super.eIsSet(featureID);
  }
-} //AllInstancesImpl
+} //CountImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DataObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DataObjectImpl.java
deleted file mode 100644
index 33bee29f..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DataObjectImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.DataObject;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Data Object</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class DataObjectImpl extends ObjectImpl implements DataObject
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected DataObjectImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.DATA_OBJECT;
-  }
-} //DataObjectImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DataSymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DataSymbolImpl.java
deleted file mode 100644
index 221b4783..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DataSymbolImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.DataSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Data Symbol</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class DataSymbolImpl extends SymbolImpl implements DataSymbol
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected DataSymbolImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.DATA_SYMBOL;
-  }
-} //DataSymbolImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DefaultDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DefaultDefinitionImpl.java
new file mode 100644
index 00000000..c1eaa71a
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DefaultDefinitionImpl.java
@@ -0,0 +1,270 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Call;
+import org.eclipse.viatra.solver.language.solverLanguage.DefaultDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Default Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.DefaultDefinitionImpl#getHead <em>Head</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.DefaultDefinitionImpl#getRange <em>Range</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class DefaultDefinitionImpl extends StatementImpl implements DefaultDefinition
+{
+  /**
+   * The cached value of the '{@link #getHead() <em>Head</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getHead()
+   * @generated
+   * @ordered
+   */
+  protected Call head;
+  /**
+   * The cached value of the '{@link #getRange() <em>Range</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getRange()
+   * @generated
+   * @ordered
+   */
+  protected Expression range;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected DefaultDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.DEFAULT_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Call getHead()
+  {
+    return head;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetHead(Call newHead, NotificationChain msgs)
+  {
+    Call oldHead = head;
+    head = newHead;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.DEFAULT_DEFINITION__HEAD, oldHead, newHead);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setHead(Call newHead)
+  {
+    if (newHead != head)
+    {
+      NotificationChain msgs = null;
+      if (head != null)
+        msgs = ((InternalEObject)head).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.DEFAULT_DEFINITION__HEAD, null, msgs);
+      if (newHead != null)
+        msgs = ((InternalEObject)newHead).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.DEFAULT_DEFINITION__HEAD, null, msgs);
+      msgs = basicSetHead(newHead, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.DEFAULT_DEFINITION__HEAD, newHead, newHead));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getRange()
+  {
+    return range;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetRange(Expression newRange, NotificationChain msgs)
+  {
+    Expression oldRange = range;
+    range = newRange;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.DEFAULT_DEFINITION__RANGE, oldRange, newRange);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setRange(Expression newRange)
+  {
+    if (newRange != range)
+    {
+      NotificationChain msgs = null;
+      if (range != null)
+        msgs = ((InternalEObject)range).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.DEFAULT_DEFINITION__RANGE, null, msgs);
+      if (newRange != null)
+        msgs = ((InternalEObject)newRange).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.DEFAULT_DEFINITION__RANGE, null, msgs);
+      msgs = basicSetRange(newRange, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.DEFAULT_DEFINITION__RANGE, newRange, newRange));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DEFAULT_DEFINITION__HEAD:
+        return basicSetHead(null, msgs);
+      case SolverLanguagePackage.DEFAULT_DEFINITION__RANGE:
+        return basicSetRange(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DEFAULT_DEFINITION__HEAD:
+        return getHead();
+      case SolverLanguagePackage.DEFAULT_DEFINITION__RANGE:
+        return getRange();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DEFAULT_DEFINITION__HEAD:
+        setHead((Call)newValue);
+        return;
+      case SolverLanguagePackage.DEFAULT_DEFINITION__RANGE:
+        setRange((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DEFAULT_DEFINITION__HEAD:
+        setHead((Call)null);
+        return;
+      case SolverLanguagePackage.DEFAULT_DEFINITION__RANGE:
+        setRange((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DEFAULT_DEFINITION__HEAD:
+        return head != null;
+      case SolverLanguagePackage.DEFAULT_DEFINITION__RANGE:
+        return range != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //DefaultDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DisjunctionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DisjunctionImpl.java
new file mode 100644
index 00000000..ecdb14d8
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DisjunctionImpl.java
@@ -0,0 +1,167 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import java.util.Collection;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.common.util.EList;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.util.EObjectContainmentEList;
+import org.eclipse.emf.ecore.util.InternalEList;
+import org.eclipse.viatra.solver.language.solverLanguage.Disjunction;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Disjunction</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.DisjunctionImpl#getChildren <em>Children</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class DisjunctionImpl extends ExpressionImpl implements Disjunction
+{
+  /**
+   * The cached value of the '{@link #getChildren() <em>Children</em>}' containment reference list.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getChildren()
+   * @generated
+   * @ordered
+   */
+  protected EList<Expression> children;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected DisjunctionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.DISJUNCTION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EList<Expression> getChildren()
+  {
+    if (children == null)
+    {
+      children = new EObjectContainmentEList<Expression>(Expression.class, this, SolverLanguagePackage.DISJUNCTION__CHILDREN);
+    }
+    return children;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DISJUNCTION__CHILDREN:
+        return ((InternalEList<?>)getChildren()).basicRemove(otherEnd, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DISJUNCTION__CHILDREN:
+        return getChildren();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @SuppressWarnings("unchecked")
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DISJUNCTION__CHILDREN:
+        getChildren().clear();
+        getChildren().addAll((Collection<? extends Expression>)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DISJUNCTION__CHILDREN:
+        getChildren().clear();
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.DISJUNCTION__CHILDREN:
+        return children != null && !children.isEmpty();
+    }
+    return super.eIsSet(featureID);
+  }
+} //DisjunctionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnknownImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/EmptyIntervalLiteralImpl.java
index 44195feb..1ebf38ad 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnknownImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/EmptyIntervalLiteralImpl.java
@@ -1,28 +1,28 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
 import org.eclipse.emf.ecore.EClass;
+import org.eclipse.viatra.solver.language.solverLanguage.EmptyIntervalLiteral;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Unknown;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Unknown</b></em>'.
+ * An implementation of the model object '<em><b>Empty Interval Literal</b></em>'.
 * <!-- end-user-doc -->
 *
 * @generated
 */
-public class UnknownImpl extends TruthValueImpl implements Unknown
+public class EmptyIntervalLiteralImpl extends LiteralImpl implements EmptyIntervalLiteral
 {
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected UnknownImpl()
+  protected EmptyIntervalLiteralImpl()
  {
    super();
  }
@@ -35,7 +35,7 @@ public class UnknownImpl extends TruthValueImpl implements Unknown
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.UNKNOWN;
+    return SolverLanguagePackage.Literals.EMPTY_INTERVAL_LITERAL;
  }
-} //UnknownImpl
+} //EmptyIntervalLiteralImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/EnumInterpretationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/EnumInterpretationImpl.java
deleted file mode 100644
index efa12ea6..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/EnumInterpretationImpl.java
+++ /dev/null
@@ -1,244 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import java.util.Collection;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.common.notify.NotificationChain;
-import org.eclipse.emf.common.util.EList;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.InternalEObject;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.util.EObjectContainmentEList;
-import org.eclipse.emf.ecore.util.InternalEList;
-import org.eclipse.viatra.solver.language.solverLanguage.EnumInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.NamedObject;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Enum Interpretation</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.EnumInterpretationImpl#getSymbol <em>Symbol</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.EnumInterpretationImpl#getObjects <em>Objects</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class EnumInterpretationImpl extends CDInterpretationImpl implements EnumInterpretation
-{
-  /**
-   * The cached value of the '{@link #getSymbol() <em>Symbol</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSymbol()
-   * @generated
-   * @ordered
-   */
-  protected ModelSymbol symbol;
-  /**
-   * The cached value of the '{@link #getObjects() <em>Objects</em>}' containment reference list.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getObjects()
-   * @generated
-   * @ordered
-   */
-  protected EList<NamedObject> objects;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected EnumInterpretationImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.ENUM_INTERPRETATION;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public ModelSymbol getSymbol()
-  {
-    return symbol;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSymbol(ModelSymbol newSymbol, NotificationChain msgs)
-  {
-    ModelSymbol oldSymbol = symbol;
-    symbol = newSymbol;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL, oldSymbol, newSymbol);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSymbol(ModelSymbol newSymbol)
-  {
-    if (newSymbol != symbol)
-    {
-      NotificationChain msgs = null;
-      if (symbol != null)
-        msgs = ((InternalEObject)symbol).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL, null, msgs);
-      if (newSymbol != null)
-        msgs = ((InternalEObject)newSymbol).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL, null, msgs);
-      msgs = basicSetSymbol(newSymbol, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL, newSymbol, newSymbol));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public EList<NamedObject> getObjects()
-  {
-    if (objects == null)
-    {
-      objects = new EObjectContainmentEList<NamedObject>(NamedObject.class, this, SolverLanguagePackage.ENUM_INTERPRETATION__OBJECTS);
-    }
-    return objects;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL:
-        return basicSetSymbol(null, msgs);
-      case SolverLanguagePackage.ENUM_INTERPRETATION__OBJECTS:
-        return ((InternalEList<?>)getObjects()).basicRemove(otherEnd, msgs);
-    }
-    return super.eInverseRemove(otherEnd, featureID, msgs);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL:
-        return getSymbol();
-      case SolverLanguagePackage.ENUM_INTERPRETATION__OBJECTS:
-        return getObjects();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @SuppressWarnings("unchecked")
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL:
-        setSymbol((ModelSymbol)newValue);
-        return;
-      case SolverLanguagePackage.ENUM_INTERPRETATION__OBJECTS:
-        getObjects().clear();
-        getObjects().addAll((Collection<? extends NamedObject>)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL:
-        setSymbol((ModelSymbol)null);
-        return;
-      case SolverLanguagePackage.ENUM_INTERPRETATION__OBJECTS:
-        getObjects().clear();
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.ENUM_INTERPRETATION__SYMBOL:
-        return symbol != null;
-      case SolverLanguagePackage.ENUM_INTERPRETATION__OBJECTS:
-        return objects != null && !objects.isEmpty();
-    }
-    return super.eIsSet(featureID);
-  }
-} //EnumInterpretationImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/EqualsSymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/EqualsSymbolImpl.java
deleted file mode 100644
index 33929f42..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/EqualsSymbolImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.EqualsSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Equals Symbol</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class EqualsSymbolImpl extends PartialitySymbolImpl implements EqualsSymbol
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected EqualsSymbolImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.EQUALS_SYMBOL;
-  }
-} //EqualsSymbolImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ErrorImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ErrorImpl.java
deleted file mode 100644
index e58094a7..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ErrorImpl.java
+++ /dev/null
@@ -1,40 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Error</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class ErrorImpl extends TruthValueImpl implements org.eclipse.viatra.solver.language.solverLanguage.Error
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected ErrorImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.ERROR;
-  }
-} //ErrorImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ModelSymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExactMultiplicityImpl.java
index bd195572..3751de39 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ModelSymbolImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExactMultiplicityImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -9,50 +9,50 @@ import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.ExactMultiplicity;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Model Symbol</b></em>'.
+ * An implementation of the model object '<em><b>Exact Multiplicity</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ModelSymbolImpl#getName <em>Name</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ExactMultiplicityImpl#getMultiplicity <em>Multiplicity</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
+public class ExactMultiplicityImpl extends MultiplicityImpl implements ExactMultiplicity
 {
  /**
-   * The default value of the '{@link #getName() <em>Name</em>}' attribute.
+   * The default value of the '{@link #getMultiplicity() <em>Multiplicity</em>}' attribute.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getName()
+   * @see #getMultiplicity()
   * @generated
   * @ordered
   */
-  protected static final String NAME_EDEFAULT = null;
+  protected static final int MULTIPLICITY_EDEFAULT = 0;
  /**
-   * The cached value of the '{@link #getName() <em>Name</em>}' attribute.
+   * The cached value of the '{@link #getMultiplicity() <em>Multiplicity</em>}' attribute.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getName()
+   * @see #getMultiplicity()
   * @generated
   * @ordered
   */
-  protected String name = NAME_EDEFAULT;
+  protected int multiplicity = MULTIPLICITY_EDEFAULT;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected ModelSymbolImpl()
+  protected ExactMultiplicityImpl()
  {
    super();
  }
@@ -65,7 +65,7 @@ public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.MODEL_SYMBOL;
+    return SolverLanguagePackage.Literals.EXACT_MULTIPLICITY;
  }
  /**
@@ -74,9 +74,9 @@ public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
   * @generated
   */
  @Override
-  public String getName()
+  public int getMultiplicity()
  {
-    return name;
+    return multiplicity;
  }
  /**
@@ -85,12 +85,12 @@ public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
   * @generated
   */
  @Override
-  public void setName(String newName)
+  public void setMultiplicity(int newMultiplicity)
  {
-    String oldName = name;
+    int oldMultiplicity = multiplicity;
-    name = newName;
+    multiplicity = newMultiplicity;
    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MODEL_SYMBOL__NAME, oldName, name));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXACT_MULTIPLICITY__MULTIPLICITY, oldMultiplicity, multiplicity));
  }
  /**
@@ -103,8 +103,8 @@ public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.MODEL_SYMBOL__NAME:
+      case SolverLanguagePackage.EXACT_MULTIPLICITY__MULTIPLICITY:
-        return getName();
+        return getMultiplicity();
    }
    return super.eGet(featureID, resolve, coreType);
  }
@@ -119,8 +119,8 @@ public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.MODEL_SYMBOL__NAME:
+      case SolverLanguagePackage.EXACT_MULTIPLICITY__MULTIPLICITY:
-        setName((String)newValue);
+        setMultiplicity((Integer)newValue);
        return;
    }
    super.eSet(featureID, newValue);
@@ -136,8 +136,8 @@ public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.MODEL_SYMBOL__NAME:
+      case SolverLanguagePackage.EXACT_MULTIPLICITY__MULTIPLICITY:
-        setName(NAME_EDEFAULT);
+        setMultiplicity(MULTIPLICITY_EDEFAULT);
        return;
    }
    super.eUnset(featureID);
@@ -153,8 +153,8 @@ public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.MODEL_SYMBOL__NAME:
+      case SolverLanguagePackage.EXACT_MULTIPLICITY__MULTIPLICITY:
-        return NAME_EDEFAULT == null ? name != null : !NAME_EDEFAULT.equals(name);
+        return multiplicity != MULTIPLICITY_EDEFAULT;
    }
    return super.eIsSet(featureID);
  }
@@ -170,10 +170,10 @@ public class ModelSymbolImpl extends SymbolImpl implements ModelSymbol
    if (eIsProxy()) return super.toString();
    StringBuilder result = new StringBuilder(super.toString());
-    result.append(" (name: ");
+    result.append(" (multiplicity: ");
-    result.append(name);
+    result.append(multiplicity);
    result.append(')');
    return result.toString();
  }
-} //ModelSymbolImpl
+} //ExactMultiplicityImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/NamedObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExactScopeDefinitionImpl.java
index 9d907661..faf51904 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/NamedObjectImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExactScopeDefinitionImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -9,50 +9,50 @@ import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.NamedObject;
+import org.eclipse.viatra.solver.language.solverLanguage.ExactScopeDefinition;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Named Object</b></em>'.
+ * An implementation of the model object '<em><b>Exact Scope Definition</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.NamedObjectImpl#getName <em>Name</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ExactScopeDefinitionImpl#getExactScope <em>Exact Scope</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class NamedObjectImpl extends ObjectImpl implements NamedObject
+public class ExactScopeDefinitionImpl extends ScopeDefinitionImpl implements ExactScopeDefinition
 {
  /**
-   * The default value of the '{@link #getName() <em>Name</em>}' attribute.
+   * The default value of the '{@link #getExactScope() <em>Exact Scope</em>}' attribute.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getName()
+   * @see #getExactScope()
   * @generated
   * @ordered
   */
-  protected static final String NAME_EDEFAULT = null;
+  protected static final int EXACT_SCOPE_EDEFAULT = 0;
  /**
-   * The cached value of the '{@link #getName() <em>Name</em>}' attribute.
+   * The cached value of the '{@link #getExactScope() <em>Exact Scope</em>}' attribute.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getName()
+   * @see #getExactScope()
   * @generated
   * @ordered
   */
-  protected String name = NAME_EDEFAULT;
+  protected int exactScope = EXACT_SCOPE_EDEFAULT;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected NamedObjectImpl()
+  protected ExactScopeDefinitionImpl()
  {
    super();
  }
@@ -65,7 +65,7 @@ public class NamedObjectImpl extends ObjectImpl implements NamedObject
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.NAMED_OBJECT;
+    return SolverLanguagePackage.Literals.EXACT_SCOPE_DEFINITION;
  }
  /**
@@ -74,9 +74,9 @@ public class NamedObjectImpl extends ObjectImpl implements NamedObject
   * @generated
   */
  @Override
-  public String getName()
+  public int getExactScope()
  {
-    return name;
+    return exactScope;
  }
  /**
@@ -85,12 +85,12 @@ public class NamedObjectImpl extends ObjectImpl implements NamedObject
   * @generated
   */
  @Override
-  public void setName(String newName)
+  public void setExactScope(int newExactScope)
  {
-    String oldName = name;
+    int oldExactScope = exactScope;
-    name = newName;
+    exactScope = newExactScope;
    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.NAMED_OBJECT__NAME, oldName, name));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXACT_SCOPE_DEFINITION__EXACT_SCOPE, oldExactScope, exactScope));
  }
  /**
@@ -103,8 +103,8 @@ public class NamedObjectImpl extends ObjectImpl implements NamedObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.NAMED_OBJECT__NAME:
+      case SolverLanguagePackage.EXACT_SCOPE_DEFINITION__EXACT_SCOPE:
-        return getName();
+        return getExactScope();
    }
    return super.eGet(featureID, resolve, coreType);
  }
@@ -119,8 +119,8 @@ public class NamedObjectImpl extends ObjectImpl implements NamedObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.NAMED_OBJECT__NAME:
+      case SolverLanguagePackage.EXACT_SCOPE_DEFINITION__EXACT_SCOPE:
-        setName((String)newValue);
+        setExactScope((Integer)newValue);
        return;
    }
    super.eSet(featureID, newValue);
@@ -136,8 +136,8 @@ public class NamedObjectImpl extends ObjectImpl implements NamedObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.NAMED_OBJECT__NAME:
+      case SolverLanguagePackage.EXACT_SCOPE_DEFINITION__EXACT_SCOPE:
-        setName(NAME_EDEFAULT);
+        setExactScope(EXACT_SCOPE_EDEFAULT);
        return;
    }
    super.eUnset(featureID);
@@ -153,8 +153,8 @@ public class NamedObjectImpl extends ObjectImpl implements NamedObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.NAMED_OBJECT__NAME:
+      case SolverLanguagePackage.EXACT_SCOPE_DEFINITION__EXACT_SCOPE:
-        return NAME_EDEFAULT == null ? name != null : !NAME_EDEFAULT.equals(name);
+        return exactScope != EXACT_SCOPE_EDEFAULT;
    }
    return super.eIsSet(featureID);
  }
@@ -170,10 +170,10 @@ public class NamedObjectImpl extends ObjectImpl implements NamedObject
    if (eIsProxy()) return super.toString();
    StringBuilder result = new StringBuilder(super.toString());
-    result.append(" (name: ");
+    result.append(" (exactScope: ");
-    result.append(name);
+    result.append(exactScope);
    result.append(')');
    return result.toString();
  }
-} //NamedObjectImpl
+} //ExactScopeDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExistSymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExistSymbolImpl.java
deleted file mode 100644
index 2fd59e41..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExistSymbolImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.ExistSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Exist Symbol</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class ExistSymbolImpl extends PartialitySymbolImpl implements ExistSymbol
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected ExistSymbolImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.EXIST_SYMBOL;
-  }
-} //ExistSymbolImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExpressionArgumentImpl.java
index cb1a3ff4..f83c1cb3 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanObjectImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExpressionArgumentImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -11,41 +11,41 @@ import org.eclipse.emf.ecore.InternalEObject;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanObject;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanValue;
+import org.eclipse.viatra.solver.language.solverLanguage.ExpressionArgument;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Boolean Object</b></em>'.
+ * An implementation of the model object '<em><b>Expression Argument</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.BooleanObjectImpl#getValue <em>Value</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ExpressionArgumentImpl#getBody <em>Body</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
+public class ExpressionArgumentImpl extends ArgumentImpl implements ExpressionArgument
 {
  /**
-   * The cached value of the '{@link #getValue() <em>Value</em>}' containment reference.
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getValue()
+   * @see #getBody()
   * @generated
   * @ordered
   */
-  protected BooleanValue value;
+  protected Expression body;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected BooleanObjectImpl()
+  protected ExpressionArgumentImpl()
  {
    super();
  }
@@ -58,7 +58,7 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.BOOLEAN_OBJECT;
+    return SolverLanguagePackage.Literals.EXPRESSION_ARGUMENT;
  }
  /**
@@ -67,9 +67,9 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
   * @generated
   */
  @Override
-  public BooleanValue getValue()
+  public Expression getBody()
  {
-    return value;
+    return body;
  }
  /**
@@ -77,13 +77,13 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
   * <!-- end-user-doc -->
   * @generated
   */
-  public NotificationChain basicSetValue(BooleanValue newValue, NotificationChain msgs)
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
  {
-    BooleanValue oldValue = value;
+    Expression oldBody = body;
-    value = newValue;
+    body = newBody;
    if (eNotificationRequired())
    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BOOLEAN_OBJECT__VALUE, oldValue, newValue);
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY, oldBody, newBody);
      if (msgs == null) msgs = notification; else msgs.add(notification);
    }
    return msgs;
@@ -95,20 +95,20 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
   * @generated
   */
  @Override
-  public void setValue(BooleanValue newValue)
+  public void setBody(Expression newBody)
  {
-    if (newValue != value)
+    if (newBody != body)
    {
      NotificationChain msgs = null;
-      if (value != null)
+      if (body != null)
-        msgs = ((InternalEObject)value).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BOOLEAN_OBJECT__VALUE, null, msgs);
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY, null, msgs);
-      if (newValue != null)
+      if (newBody != null)
-        msgs = ((InternalEObject)newValue).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.BOOLEAN_OBJECT__VALUE, null, msgs);
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY, null, msgs);
-      msgs = basicSetValue(newValue, msgs);
+      msgs = basicSetBody(newBody, msgs);
      if (msgs != null) msgs.dispatch();
    }
    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.BOOLEAN_OBJECT__VALUE, newValue, newValue));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY, newBody, newBody));
  }
  /**
@@ -121,8 +121,8 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.BOOLEAN_OBJECT__VALUE:
+      case SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY:
-        return basicSetValue(null, msgs);
+        return basicSetBody(null, msgs);
    }
    return super.eInverseRemove(otherEnd, featureID, msgs);
  }
@@ -137,8 +137,8 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.BOOLEAN_OBJECT__VALUE:
+      case SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY:
-        return getValue();
+        return getBody();
    }
    return super.eGet(featureID, resolve, coreType);
  }
@@ -153,8 +153,8 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.BOOLEAN_OBJECT__VALUE:
+      case SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY:
-        setValue((BooleanValue)newValue);
+        setBody((Expression)newValue);
        return;
    }
    super.eSet(featureID, newValue);
@@ -170,8 +170,8 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.BOOLEAN_OBJECT__VALUE:
+      case SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY:
-        setValue((BooleanValue)null);
+        setBody((Expression)null);
        return;
    }
    super.eUnset(featureID);
@@ -187,10 +187,10 @@ public class BooleanObjectImpl extends DataObjectImpl implements BooleanObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.BOOLEAN_OBJECT__VALUE:
+      case SolverLanguagePackage.EXPRESSION_ARGUMENT__BODY:
-        return value != null;
+        return body != null;
    }
    return super.eIsSet(featureID);
  }
-} //BooleanObjectImpl
+} //ExpressionArgumentImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/NegativeImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExpressionImpl.java
index a30b228f..585e3c41 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/NegativeImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExpressionImpl.java
@@ -1,28 +1,28 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
 import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.Negative;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Negative</b></em>'.
+ * An implementation of the model object '<em><b>Expression</b></em>'.
 * <!-- end-user-doc -->
 *
 * @generated
 */
-public class NegativeImpl extends PolarityImpl implements Negative
+public class ExpressionImpl extends StatementImpl implements Expression
 {
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected NegativeImpl()
+  protected ExpressionImpl()
  {
    super();
  }
@@ -35,7 +35,7 @@ public class NegativeImpl extends PolarityImpl implements Negative
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.NEGATIVE;
+    return SolverLanguagePackage.Literals.EXPRESSION;
  }
-} //NegativeImpl
+} //ExpressionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExternMetricDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExternMetricDefinitionImpl.java
new file mode 100644
index 00000000..e324c38a
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExternMetricDefinitionImpl.java
@@ -0,0 +1,270 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Call;
+import org.eclipse.viatra.solver.language.solverLanguage.ExternMetricDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.MetricType;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Extern Metric Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ExternMetricDefinitionImpl#getType <em>Type</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ExternMetricDefinitionImpl#getHead <em>Head</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class ExternMetricDefinitionImpl extends StatementImpl implements ExternMetricDefinition
+{
+  /**
+   * The default value of the '{@link #getType() <em>Type</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getType()
+   * @generated
+   * @ordered
+   */
+  protected static final MetricType TYPE_EDEFAULT = MetricType.INT;
+  /**
+   * The cached value of the '{@link #getType() <em>Type</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getType()
+   * @generated
+   * @ordered
+   */
+  protected MetricType type = TYPE_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getHead() <em>Head</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getHead()
+   * @generated
+   * @ordered
+   */
+  protected Call head;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected ExternMetricDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.EXTERN_METRIC_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public MetricType getType()
+  {
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setType(MetricType newType)
+  {
+    MetricType oldType = type;
+    type = newType == null ? TYPE_EDEFAULT : newType;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXTERN_METRIC_DEFINITION__TYPE, oldType, type));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Call getHead()
+  {
+    return head;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetHead(Call newHead, NotificationChain msgs)
+  {
+    Call oldHead = head;
+    head = newHead;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD, oldHead, newHead);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setHead(Call newHead)
+  {
+    if (newHead != head)
+    {
+      NotificationChain msgs = null;
+      if (head != null)
+        msgs = ((InternalEObject)head).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD, null, msgs);
+      if (newHead != null)
+        msgs = ((InternalEObject)newHead).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD, null, msgs);
+      msgs = basicSetHead(newHead, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD, newHead, newHead));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD:
+        return basicSetHead(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__TYPE:
+        return getType();
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD:
+        return getHead();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__TYPE:
+        setType((MetricType)newValue);
+        return;
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD:
+        setHead((Call)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__TYPE:
+        setType(TYPE_EDEFAULT);
+        return;
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD:
+        setHead((Call)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__TYPE:
+        return type != TYPE_EDEFAULT;
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION__HEAD:
+        return head != null;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (type: ");
+    result.append(type);
+    result.append(')');
+    return result.toString();
+  }
+} //ExternMetricDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DefaultInterpretationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExternPredicateDefinitionImpl.java
index eb2835a0..0605cb0f 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/DefaultInterpretationImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ExternPredicateDefinitionImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -11,41 +11,41 @@ import org.eclipse.emf.ecore.InternalEObject;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.BasicInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.Call;
-import org.eclipse.viatra.solver.language.solverLanguage.DefaultInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.ExternPredicateDefinition;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Default Interpretation</b></em>'.
+ * An implementation of the model object '<em><b>Extern Predicate Definition</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.DefaultInterpretationImpl#getInterpretation <em>Interpretation</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ExternPredicateDefinitionImpl#getHead <em>Head</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class DefaultInterpretationImpl extends InterpretationImpl implements DefaultInterpretation
+public class ExternPredicateDefinitionImpl extends StatementImpl implements ExternPredicateDefinition
 {
  /**
-   * The cached value of the '{@link #getInterpretation() <em>Interpretation</em>}' containment reference.
+   * The cached value of the '{@link #getHead() <em>Head</em>}' containment reference.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
-   * @see #getInterpretation()
+   * @see #getHead()
   * @generated
   * @ordered
   */
-  protected BasicInterpretation interpretation;
+  protected Call head;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected DefaultInterpretationImpl()
+  protected ExternPredicateDefinitionImpl()
  {
    super();
  }
@@ -58,7 +58,7 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.DEFAULT_INTERPRETATION;
+    return SolverLanguagePackage.Literals.EXTERN_PREDICATE_DEFINITION;
  }
  /**
@@ -67,9 +67,9 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
   * @generated
   */
  @Override
-  public BasicInterpretation getInterpretation()
+  public Call getHead()
  {
-    return interpretation;
+    return head;
  }
  /**
@@ -77,13 +77,13 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
   * <!-- end-user-doc -->
   * @generated
   */
-  public NotificationChain basicSetInterpretation(BasicInterpretation newInterpretation, NotificationChain msgs)
+  public NotificationChain basicSetHead(Call newHead, NotificationChain msgs)
  {
-    BasicInterpretation oldInterpretation = interpretation;
+    Call oldHead = head;
-    interpretation = newInterpretation;
+    head = newHead;
    if (eNotificationRequired())
    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION, oldInterpretation, newInterpretation);
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD, oldHead, newHead);
      if (msgs == null) msgs = notification; else msgs.add(notification);
    }
    return msgs;
@@ -95,20 +95,20 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
   * @generated
   */
  @Override
-  public void setInterpretation(BasicInterpretation newInterpretation)
+  public void setHead(Call newHead)
  {
-    if (newInterpretation != interpretation)
+    if (newHead != head)
    {
      NotificationChain msgs = null;
-      if (interpretation != null)
+      if (head != null)
-        msgs = ((InternalEObject)interpretation).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION, null, msgs);
+        msgs = ((InternalEObject)head).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD, null, msgs);
-      if (newInterpretation != null)
+      if (newHead != null)
-        msgs = ((InternalEObject)newInterpretation).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION, null, msgs);
+        msgs = ((InternalEObject)newHead).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD, null, msgs);
-      msgs = basicSetInterpretation(newInterpretation, msgs);
+      msgs = basicSetHead(newHead, msgs);
      if (msgs != null) msgs.dispatch();
    }
    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION, newInterpretation, newInterpretation));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD, newHead, newHead));
  }
  /**
@@ -121,8 +121,8 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION:
+      case SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD:
-        return basicSetInterpretation(null, msgs);
+        return basicSetHead(null, msgs);
    }
    return super.eInverseRemove(otherEnd, featureID, msgs);
  }
@@ -137,8 +137,8 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION:
+      case SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD:
-        return getInterpretation();
+        return getHead();
    }
    return super.eGet(featureID, resolve, coreType);
  }
@@ -153,8 +153,8 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION:
+      case SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD:
-        setInterpretation((BasicInterpretation)newValue);
+        setHead((Call)newValue);
        return;
    }
    super.eSet(featureID, newValue);
@@ -170,8 +170,8 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION:
+      case SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD:
-        setInterpretation((BasicInterpretation)null);
+        setHead((Call)null);
        return;
    }
    super.eUnset(featureID);
@@ -187,10 +187,10 @@ public class DefaultInterpretationImpl extends InterpretationImpl implements Def
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.DEFAULT_INTERPRETATION__INTERPRETATION:
+      case SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION__HEAD:
-        return interpretation != null;
+        return head != null;
    }
    return super.eIsSet(featureID);
  }
-} //DefaultInterpretationImpl
+} //ExternPredicateDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/FalseImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/FalseImpl.java
deleted file mode 100644
index 332f9af3..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/FalseImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.False;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>False</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class FalseImpl extends TruthValueImpl implements False
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected FalseImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.FALSE;
-  }
-} //FalseImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/FieldRelationInterpretationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/FieldRelationInterpretationImpl.java
deleted file mode 100644
index ea9b80b2..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/FieldRelationInterpretationImpl.java
+++ /dev/null
@@ -1,418 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.common.notify.NotificationChain;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.InternalEObject;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.FieldRelationInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.MultiplicityDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Symbol;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Field Relation Interpretation</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.FieldRelationInterpretationImpl#isContainment <em>Containment</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.FieldRelationInterpretationImpl#getSymbol <em>Symbol</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.FieldRelationInterpretationImpl#getMultiplicity <em>Multiplicity</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.FieldRelationInterpretationImpl#getTarget <em>Target</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class FieldRelationInterpretationImpl extends MinimalEObjectImpl.Container implements FieldRelationInterpretation
-{
-  /**
-   * The default value of the '{@link #isContainment() <em>Containment</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isContainment()
-   * @generated
-   * @ordered
-   */
-  protected static final boolean CONTAINMENT_EDEFAULT = false;
-  /**
-   * The cached value of the '{@link #isContainment() <em>Containment</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isContainment()
-   * @generated
-   * @ordered
-   */
-  protected boolean containment = CONTAINMENT_EDEFAULT;
-  /**
-   * The cached value of the '{@link #getSymbol() <em>Symbol</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSymbol()
-   * @generated
-   * @ordered
-   */
-  protected ModelSymbol symbol;
-  /**
-   * The cached value of the '{@link #getMultiplicity() <em>Multiplicity</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getMultiplicity()
-   * @generated
-   * @ordered
-   */
-  protected MultiplicityDefinition multiplicity;
-  /**
-   * The cached value of the '{@link #getTarget() <em>Target</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getTarget()
-   * @generated
-   * @ordered
-   */
-  protected Symbol target;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected FieldRelationInterpretationImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.FIELD_RELATION_INTERPRETATION;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean isContainment()
-  {
-    return containment;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setContainment(boolean newContainment)
-  {
-    boolean oldContainment = containment;
-    containment = newContainment;
-    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__CONTAINMENT, oldContainment, containment));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public ModelSymbol getSymbol()
-  {
-    return symbol;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSymbol(ModelSymbol newSymbol, NotificationChain msgs)
-  {
-    ModelSymbol oldSymbol = symbol;
-    symbol = newSymbol;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL, oldSymbol, newSymbol);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSymbol(ModelSymbol newSymbol)
-  {
-    if (newSymbol != symbol)
-    {
-      NotificationChain msgs = null;
-      if (symbol != null)
-        msgs = ((InternalEObject)symbol).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL, null, msgs);
-      if (newSymbol != null)
-        msgs = ((InternalEObject)newSymbol).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL, null, msgs);
-      msgs = basicSetSymbol(newSymbol, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL, newSymbol, newSymbol));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public MultiplicityDefinition getMultiplicity()
-  {
-    return multiplicity;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetMultiplicity(MultiplicityDefinition newMultiplicity, NotificationChain msgs)
-  {
-    MultiplicityDefinition oldMultiplicity = multiplicity;
-    multiplicity = newMultiplicity;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY, oldMultiplicity, newMultiplicity);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setMultiplicity(MultiplicityDefinition newMultiplicity)
-  {
-    if (newMultiplicity != multiplicity)
-    {
-      NotificationChain msgs = null;
-      if (multiplicity != null)
-        msgs = ((InternalEObject)multiplicity).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY, null, msgs);
-      if (newMultiplicity != null)
-        msgs = ((InternalEObject)newMultiplicity).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY, null, msgs);
-      msgs = basicSetMultiplicity(newMultiplicity, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY, newMultiplicity, newMultiplicity));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Symbol getTarget()
-  {
-    return target;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetTarget(Symbol newTarget, NotificationChain msgs)
-  {
-    Symbol oldTarget = target;
-    target = newTarget;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET, oldTarget, newTarget);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setTarget(Symbol newTarget)
-  {
-    if (newTarget != target)
-    {
-      NotificationChain msgs = null;
-      if (target != null)
-        msgs = ((InternalEObject)target).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET, null, msgs);
-      if (newTarget != null)
-        msgs = ((InternalEObject)newTarget).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET, null, msgs);
-      msgs = basicSetTarget(newTarget, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET, newTarget, newTarget));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL:
-        return basicSetSymbol(null, msgs);
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY:
-        return basicSetMultiplicity(null, msgs);
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET:
-        return basicSetTarget(null, msgs);
-    }
-    return super.eInverseRemove(otherEnd, featureID, msgs);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__CONTAINMENT:
-        return isContainment();
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL:
-        return getSymbol();
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY:
-        return getMultiplicity();
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET:
-        return getTarget();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__CONTAINMENT:
-        setContainment((Boolean)newValue);
-        return;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL:
-        setSymbol((ModelSymbol)newValue);
-        return;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY:
-        setMultiplicity((MultiplicityDefinition)newValue);
-        return;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET:
-        setTarget((Symbol)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__CONTAINMENT:
-        setContainment(CONTAINMENT_EDEFAULT);
-        return;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL:
-        setSymbol((ModelSymbol)null);
-        return;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY:
-        setMultiplicity((MultiplicityDefinition)null);
-        return;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET:
-        setTarget((Symbol)null);
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__CONTAINMENT:
-        return containment != CONTAINMENT_EDEFAULT;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__SYMBOL:
-        return symbol != null;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__MULTIPLICITY:
-        return multiplicity != null;
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION__TARGET:
-        return target != null;
-    }
-    return super.eIsSet(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public String toString()
-  {
-    if (eIsProxy()) return super.toString();
-    StringBuilder result = new StringBuilder(super.toString());
-    result.append(" (containment: ");
-    result.append(containment);
-    result.append(')');
-    return result.toString();
-  }
-} //FieldRelationInterpretationImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/GlobalRelationInterpretationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/GlobalRelationInterpretationImpl.java
deleted file mode 100644
index 52f7a67d..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/GlobalRelationInterpretationImpl.java
+++ /dev/null
@@ -1,563 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.common.notify.NotificationChain;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.InternalEObject;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.GlobalRelationInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.MultiplicityDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Symbol;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Global Relation Interpretation</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.GlobalRelationInterpretationImpl#isContainment <em>Containment</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.GlobalRelationInterpretationImpl#getSymbol <em>Symbol</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.GlobalRelationInterpretationImpl#getSourceMultiplicity <em>Source Multiplicity</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.GlobalRelationInterpretationImpl#getSource <em>Source</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.GlobalRelationInterpretationImpl#getTargetMultiplicity <em>Target Multiplicity</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.GlobalRelationInterpretationImpl#getTarget <em>Target</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class GlobalRelationInterpretationImpl extends CDInterpretationImpl implements GlobalRelationInterpretation
-{
-  /**
-   * The default value of the '{@link #isContainment() <em>Containment</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isContainment()
-   * @generated
-   * @ordered
-   */
-  protected static final boolean CONTAINMENT_EDEFAULT = false;
-  /**
-   * The cached value of the '{@link #isContainment() <em>Containment</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isContainment()
-   * @generated
-   * @ordered
-   */
-  protected boolean containment = CONTAINMENT_EDEFAULT;
-  /**
-   * The cached value of the '{@link #getSymbol() <em>Symbol</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSymbol()
-   * @generated
-   * @ordered
-   */
-  protected ModelSymbol symbol;
-  /**
-   * The cached value of the '{@link #getSourceMultiplicity() <em>Source Multiplicity</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSourceMultiplicity()
-   * @generated
-   * @ordered
-   */
-  protected MultiplicityDefinition sourceMultiplicity;
-  /**
-   * The cached value of the '{@link #getSource() <em>Source</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSource()
-   * @generated
-   * @ordered
-   */
-  protected Symbol source;
-  /**
-   * The cached value of the '{@link #getTargetMultiplicity() <em>Target Multiplicity</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getTargetMultiplicity()
-   * @generated
-   * @ordered
-   */
-  protected MultiplicityDefinition targetMultiplicity;
-  /**
-   * The cached value of the '{@link #getTarget() <em>Target</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getTarget()
-   * @generated
-   * @ordered
-   */
-  protected Symbol target;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected GlobalRelationInterpretationImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.GLOBAL_RELATION_INTERPRETATION;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean isContainment()
-  {
-    return containment;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setContainment(boolean newContainment)
-  {
-    boolean oldContainment = containment;
-    containment = newContainment;
-    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__CONTAINMENT, oldContainment, containment));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public ModelSymbol getSymbol()
-  {
-    return symbol;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSymbol(ModelSymbol newSymbol, NotificationChain msgs)
-  {
-    ModelSymbol oldSymbol = symbol;
-    symbol = newSymbol;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL, oldSymbol, newSymbol);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSymbol(ModelSymbol newSymbol)
-  {
-    if (newSymbol != symbol)
-    {
-      NotificationChain msgs = null;
-      if (symbol != null)
-        msgs = ((InternalEObject)symbol).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL, null, msgs);
-      if (newSymbol != null)
-        msgs = ((InternalEObject)newSymbol).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL, null, msgs);
-      msgs = basicSetSymbol(newSymbol, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL, newSymbol, newSymbol));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public MultiplicityDefinition getSourceMultiplicity()
-  {
-    return sourceMultiplicity;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSourceMultiplicity(MultiplicityDefinition newSourceMultiplicity, NotificationChain msgs)
-  {
-    MultiplicityDefinition oldSourceMultiplicity = sourceMultiplicity;
-    sourceMultiplicity = newSourceMultiplicity;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY, oldSourceMultiplicity, newSourceMultiplicity);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSourceMultiplicity(MultiplicityDefinition newSourceMultiplicity)
-  {
-    if (newSourceMultiplicity != sourceMultiplicity)
-    {
-      NotificationChain msgs = null;
-      if (sourceMultiplicity != null)
-        msgs = ((InternalEObject)sourceMultiplicity).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY, null, msgs);
-      if (newSourceMultiplicity != null)
-        msgs = ((InternalEObject)newSourceMultiplicity).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY, null, msgs);
-      msgs = basicSetSourceMultiplicity(newSourceMultiplicity, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY, newSourceMultiplicity, newSourceMultiplicity));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Symbol getSource()
-  {
-    return source;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSource(Symbol newSource, NotificationChain msgs)
-  {
-    Symbol oldSource = source;
-    source = newSource;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE, oldSource, newSource);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSource(Symbol newSource)
-  {
-    if (newSource != source)
-    {
-      NotificationChain msgs = null;
-      if (source != null)
-        msgs = ((InternalEObject)source).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE, null, msgs);
-      if (newSource != null)
-        msgs = ((InternalEObject)newSource).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE, null, msgs);
-      msgs = basicSetSource(newSource, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE, newSource, newSource));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public MultiplicityDefinition getTargetMultiplicity()
-  {
-    return targetMultiplicity;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetTargetMultiplicity(MultiplicityDefinition newTargetMultiplicity, NotificationChain msgs)
-  {
-    MultiplicityDefinition oldTargetMultiplicity = targetMultiplicity;
-    targetMultiplicity = newTargetMultiplicity;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY, oldTargetMultiplicity, newTargetMultiplicity);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setTargetMultiplicity(MultiplicityDefinition newTargetMultiplicity)
-  {
-    if (newTargetMultiplicity != targetMultiplicity)
-    {
-      NotificationChain msgs = null;
-      if (targetMultiplicity != null)
-        msgs = ((InternalEObject)targetMultiplicity).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY, null, msgs);
-      if (newTargetMultiplicity != null)
-        msgs = ((InternalEObject)newTargetMultiplicity).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY, null, msgs);
-      msgs = basicSetTargetMultiplicity(newTargetMultiplicity, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY, newTargetMultiplicity, newTargetMultiplicity));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Symbol getTarget()
-  {
-    return target;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetTarget(Symbol newTarget, NotificationChain msgs)
-  {
-    Symbol oldTarget = target;
-    target = newTarget;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET, oldTarget, newTarget);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setTarget(Symbol newTarget)
-  {
-    if (newTarget != target)
-    {
-      NotificationChain msgs = null;
-      if (target != null)
-        msgs = ((InternalEObject)target).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET, null, msgs);
-      if (newTarget != null)
-        msgs = ((InternalEObject)newTarget).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET, null, msgs);
-      msgs = basicSetTarget(newTarget, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET, newTarget, newTarget));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL:
-        return basicSetSymbol(null, msgs);
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY:
-        return basicSetSourceMultiplicity(null, msgs);
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE:
-        return basicSetSource(null, msgs);
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY:
-        return basicSetTargetMultiplicity(null, msgs);
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET:
-        return basicSetTarget(null, msgs);
-    }
-    return super.eInverseRemove(otherEnd, featureID, msgs);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__CONTAINMENT:
-        return isContainment();
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL:
-        return getSymbol();
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY:
-        return getSourceMultiplicity();
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE:
-        return getSource();
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY:
-        return getTargetMultiplicity();
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET:
-        return getTarget();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__CONTAINMENT:
-        setContainment((Boolean)newValue);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL:
-        setSymbol((ModelSymbol)newValue);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY:
-        setSourceMultiplicity((MultiplicityDefinition)newValue);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE:
-        setSource((Symbol)newValue);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY:
-        setTargetMultiplicity((MultiplicityDefinition)newValue);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET:
-        setTarget((Symbol)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__CONTAINMENT:
-        setContainment(CONTAINMENT_EDEFAULT);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL:
-        setSymbol((ModelSymbol)null);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY:
-        setSourceMultiplicity((MultiplicityDefinition)null);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE:
-        setSource((Symbol)null);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY:
-        setTargetMultiplicity((MultiplicityDefinition)null);
-        return;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET:
-        setTarget((Symbol)null);
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__CONTAINMENT:
-        return containment != CONTAINMENT_EDEFAULT;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SYMBOL:
-        return symbol != null;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY:
-        return sourceMultiplicity != null;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__SOURCE:
-        return source != null;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY:
-        return targetMultiplicity != null;
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION__TARGET:
-        return target != null;
-    }
-    return super.eIsSet(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public String toString()
-  {
-    if (eIsProxy()) return super.toString();
-    StringBuilder result = new StringBuilder(super.toString());
-    result.append(" (containment: ");
-    result.append(containment);
-    result.append(')');
-    return result.toString();
-  }
-} //GlobalRelationInterpretationImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IfElseImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IfElseImpl.java
new file mode 100644
index 00000000..1b873568
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IfElseImpl.java
@@ -0,0 +1,342 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.IfElse;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>If Else</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.IfElseImpl#getCondition <em>Condition</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.IfElseImpl#getThen <em>Then</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.IfElseImpl#getElse <em>Else</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class IfElseImpl extends ExpressionImpl implements IfElse
+{
+  /**
+   * The cached value of the '{@link #getCondition() <em>Condition</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getCondition()
+   * @generated
+   * @ordered
+   */
+  protected Expression condition;
+  /**
+   * The cached value of the '{@link #getThen() <em>Then</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getThen()
+   * @generated
+   * @ordered
+   */
+  protected Expression then;
+  /**
+   * The cached value of the '{@link #getElse() <em>Else</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getElse()
+   * @generated
+   * @ordered
+   */
+  protected Expression else_;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected IfElseImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.IF_ELSE;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getCondition()
+  {
+    return condition;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetCondition(Expression newCondition, NotificationChain msgs)
+  {
+    Expression oldCondition = condition;
+    condition = newCondition;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.IF_ELSE__CONDITION, oldCondition, newCondition);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setCondition(Expression newCondition)
+  {
+    if (newCondition != condition)
+    {
+      NotificationChain msgs = null;
+      if (condition != null)
+        msgs = ((InternalEObject)condition).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.IF_ELSE__CONDITION, null, msgs);
+      if (newCondition != null)
+        msgs = ((InternalEObject)newCondition).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.IF_ELSE__CONDITION, null, msgs);
+      msgs = basicSetCondition(newCondition, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.IF_ELSE__CONDITION, newCondition, newCondition));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getThen()
+  {
+    return then;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetThen(Expression newThen, NotificationChain msgs)
+  {
+    Expression oldThen = then;
+    then = newThen;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.IF_ELSE__THEN, oldThen, newThen);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setThen(Expression newThen)
+  {
+    if (newThen != then)
+    {
+      NotificationChain msgs = null;
+      if (then != null)
+        msgs = ((InternalEObject)then).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.IF_ELSE__THEN, null, msgs);
+      if (newThen != null)
+        msgs = ((InternalEObject)newThen).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.IF_ELSE__THEN, null, msgs);
+      msgs = basicSetThen(newThen, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.IF_ELSE__THEN, newThen, newThen));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getElse()
+  {
+    return else_;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetElse(Expression newElse, NotificationChain msgs)
+  {
+    Expression oldElse = else_;
+    else_ = newElse;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.IF_ELSE__ELSE, oldElse, newElse);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setElse(Expression newElse)
+  {
+    if (newElse != else_)
+    {
+      NotificationChain msgs = null;
+      if (else_ != null)
+        msgs = ((InternalEObject)else_).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.IF_ELSE__ELSE, null, msgs);
+      if (newElse != null)
+        msgs = ((InternalEObject)newElse).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.IF_ELSE__ELSE, null, msgs);
+      msgs = basicSetElse(newElse, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.IF_ELSE__ELSE, newElse, newElse));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.IF_ELSE__CONDITION:
+        return basicSetCondition(null, msgs);
+      case SolverLanguagePackage.IF_ELSE__THEN:
+        return basicSetThen(null, msgs);
+      case SolverLanguagePackage.IF_ELSE__ELSE:
+        return basicSetElse(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.IF_ELSE__CONDITION:
+        return getCondition();
+      case SolverLanguagePackage.IF_ELSE__THEN:
+        return getThen();
+      case SolverLanguagePackage.IF_ELSE__ELSE:
+        return getElse();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.IF_ELSE__CONDITION:
+        setCondition((Expression)newValue);
+        return;
+      case SolverLanguagePackage.IF_ELSE__THEN:
+        setThen((Expression)newValue);
+        return;
+      case SolverLanguagePackage.IF_ELSE__ELSE:
+        setElse((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.IF_ELSE__CONDITION:
+        setCondition((Expression)null);
+        return;
+      case SolverLanguagePackage.IF_ELSE__THEN:
+        setThen((Expression)null);
+        return;
+      case SolverLanguagePackage.IF_ELSE__ELSE:
+        setElse((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.IF_ELSE__CONDITION:
+        return condition != null;
+      case SolverLanguagePackage.IF_ELSE__THEN:
+        return then != null;
+      case SolverLanguagePackage.IF_ELSE__ELSE:
+        return else_ != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //IfElseImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanSymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/InfinityLiteralImpl.java
index 49258091..e796f5a0 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/BooleanSymbolImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/InfinityLiteralImpl.java
@@ -1,28 +1,28 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
 import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.InfinityLiteral;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Boolean Symbol</b></em>'.
+ * An implementation of the model object '<em><b>Infinity Literal</b></em>'.
 * <!-- end-user-doc -->
 *
 * @generated
 */
-public class BooleanSymbolImpl extends DataSymbolImpl implements BooleanSymbol
+public class InfinityLiteralImpl extends LiteralImpl implements InfinityLiteral
 {
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected BooleanSymbolImpl()
+  protected InfinityLiteralImpl()
  {
    super();
  }
@@ -35,7 +35,7 @@ public class BooleanSymbolImpl extends DataSymbolImpl implements BooleanSymbol
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.BOOLEAN_SYMBOL;
+    return SolverLanguagePackage.Literals.INFINITY_LITERAL;
  }
-} //BooleanSymbolImpl
+} //InfinityLiteralImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IntegerSymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IntegerSymbolImpl.java
deleted file mode 100644
index bcd978fa..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IntegerSymbolImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.IntegerSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Integer Symbol</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class IntegerSymbolImpl extends DataSymbolImpl implements IntegerSymbol
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected IntegerSymbolImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.INTEGER_SYMBOL;
-  }
-} //IntegerSymbolImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/InterpretationImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/InterpretationImpl.java
deleted file mode 100644
index fb41d77d..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/InterpretationImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.Interpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Interpretation</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class InterpretationImpl extends StatementImpl implements Interpretation
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected InterpretationImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.INTERPRETATION;
-  }
-} //InterpretationImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IntervalImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IntervalImpl.java
new file mode 100644
index 00000000..e6107ef8
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IntervalImpl.java
@@ -0,0 +1,269 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.Interval;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Interval</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.IntervalImpl#getLowerBound <em>Lower Bound</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.IntervalImpl#getUpperBound <em>Upper Bound</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class IntervalImpl extends ExpressionImpl implements Interval
+{
+  /**
+   * The cached value of the '{@link #getLowerBound() <em>Lower Bound</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLowerBound()
+   * @generated
+   * @ordered
+   */
+  protected Expression lowerBound;
+  /**
+   * The cached value of the '{@link #getUpperBound() <em>Upper Bound</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getUpperBound()
+   * @generated
+   * @ordered
+   */
+  protected Expression upperBound;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected IntervalImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.INTERVAL;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getLowerBound()
+  {
+    return lowerBound;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetLowerBound(Expression newLowerBound, NotificationChain msgs)
+  {
+    Expression oldLowerBound = lowerBound;
+    lowerBound = newLowerBound;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.INTERVAL__LOWER_BOUND, oldLowerBound, newLowerBound);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setLowerBound(Expression newLowerBound)
+  {
+    if (newLowerBound != lowerBound)
+    {
+      NotificationChain msgs = null;
+      if (lowerBound != null)
+        msgs = ((InternalEObject)lowerBound).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.INTERVAL__LOWER_BOUND, null, msgs);
+      if (newLowerBound != null)
+        msgs = ((InternalEObject)newLowerBound).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.INTERVAL__LOWER_BOUND, null, msgs);
+      msgs = basicSetLowerBound(newLowerBound, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.INTERVAL__LOWER_BOUND, newLowerBound, newLowerBound));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getUpperBound()
+  {
+    return upperBound;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetUpperBound(Expression newUpperBound, NotificationChain msgs)
+  {
+    Expression oldUpperBound = upperBound;
+    upperBound = newUpperBound;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.INTERVAL__UPPER_BOUND, oldUpperBound, newUpperBound);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setUpperBound(Expression newUpperBound)
+  {
+    if (newUpperBound != upperBound)
+    {
+      NotificationChain msgs = null;
+      if (upperBound != null)
+        msgs = ((InternalEObject)upperBound).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.INTERVAL__UPPER_BOUND, null, msgs);
+      if (newUpperBound != null)
+        msgs = ((InternalEObject)newUpperBound).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.INTERVAL__UPPER_BOUND, null, msgs);
+      msgs = basicSetUpperBound(newUpperBound, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.INTERVAL__UPPER_BOUND, newUpperBound, newUpperBound));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.INTERVAL__LOWER_BOUND:
+        return basicSetLowerBound(null, msgs);
+      case SolverLanguagePackage.INTERVAL__UPPER_BOUND:
+        return basicSetUpperBound(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.INTERVAL__LOWER_BOUND:
+        return getLowerBound();
+      case SolverLanguagePackage.INTERVAL__UPPER_BOUND:
+        return getUpperBound();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.INTERVAL__LOWER_BOUND:
+        setLowerBound((Expression)newValue);
+        return;
+      case SolverLanguagePackage.INTERVAL__UPPER_BOUND:
+        setUpperBound((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.INTERVAL__LOWER_BOUND:
+        setLowerBound((Expression)null);
+        return;
+      case SolverLanguagePackage.INTERVAL__UPPER_BOUND:
+        setUpperBound((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.INTERVAL__LOWER_BOUND:
+        return lowerBound != null;
+      case SolverLanguagePackage.INTERVAL__UPPER_BOUND:
+        return upperBound != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //IntervalImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IrreflexiveClosureImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IrreflexiveClosureImpl.java
deleted file mode 100644
index 07ad66f9..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IrreflexiveClosureImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.IrreflexiveClosure;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Irreflexive Closure</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class IrreflexiveClosureImpl extends ClosureTypeImpl implements IrreflexiveClosure
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected IrreflexiveClosureImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.IRREFLEXIVE_CLOSURE;
-  }
-} //IrreflexiveClosureImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LiteralImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LiteralImpl.java
index 518aa2b7..2983566c 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LiteralImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LiteralImpl.java
@@ -1,12 +1,10 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
 import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
 import org.eclipse.viatra.solver.language.solverLanguage.Literal;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
@@ -17,7 +15,7 @@ import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 *
 * @generated
 */
-public class LiteralImpl extends MinimalEObjectImpl.Container implements Literal
+public class LiteralImpl extends ExpressionImpl implements Literal
 {
  /**
   * <!-- begin-user-doc -->
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IntObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LogicLiteralImpl.java
index fa844b68..2bc27a20 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/IntObjectImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LogicLiteralImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -9,23 +9,24 @@ import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.IntObject;
+import org.eclipse.viatra.solver.language.solverLanguage.LogicLiteral;
+import org.eclipse.viatra.solver.language.solverLanguage.LogicValue;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Int Object</b></em>'.
+ * An implementation of the model object '<em><b>Logic Literal</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.IntObjectImpl#getValue <em>Value</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.LogicLiteralImpl#getValue <em>Value</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class IntObjectImpl extends DataObjectImpl implements IntObject
+public class LogicLiteralImpl extends LiteralImpl implements LogicLiteral
 {
  /**
   * The default value of the '{@link #getValue() <em>Value</em>}' attribute.
@@ -35,7 +36,7 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
   * @generated
   * @ordered
   */
-  protected static final int VALUE_EDEFAULT = 0;
+  protected static final LogicValue VALUE_EDEFAULT = LogicValue.TRUE;
  /**
   * The cached value of the '{@link #getValue() <em>Value</em>}' attribute.
@@ -45,14 +46,14 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
   * @generated
   * @ordered
   */
-  protected int value = VALUE_EDEFAULT;
+  protected LogicValue value = VALUE_EDEFAULT;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected IntObjectImpl()
+  protected LogicLiteralImpl()
  {
    super();
  }
@@ -65,7 +66,7 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.INT_OBJECT;
+    return SolverLanguagePackage.Literals.LOGIC_LITERAL;
  }
  /**
@@ -74,7 +75,7 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
   * @generated
   */
  @Override
-  public int getValue()
+  public LogicValue getValue()
  {
    return value;
  }
@@ -85,12 +86,12 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
   * @generated
   */
  @Override
-  public void setValue(int newValue)
+  public void setValue(LogicValue newValue)
  {
-    int oldValue = value;
+    LogicValue oldValue = value;
-    value = newValue;
+    value = newValue == null ? VALUE_EDEFAULT : newValue;
    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.INT_OBJECT__VALUE, oldValue, value));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.LOGIC_LITERAL__VALUE, oldValue, value));
  }
  /**
@@ -103,7 +104,7 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.INT_OBJECT__VALUE:
+      case SolverLanguagePackage.LOGIC_LITERAL__VALUE:
        return getValue();
    }
    return super.eGet(featureID, resolve, coreType);
@@ -119,8 +120,8 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.INT_OBJECT__VALUE:
+      case SolverLanguagePackage.LOGIC_LITERAL__VALUE:
-        setValue((Integer)newValue);
+        setValue((LogicValue)newValue);
        return;
    }
    super.eSet(featureID, newValue);
@@ -136,7 +137,7 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.INT_OBJECT__VALUE:
+      case SolverLanguagePackage.LOGIC_LITERAL__VALUE:
        setValue(VALUE_EDEFAULT);
        return;
    }
@@ -153,7 +154,7 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.INT_OBJECT__VALUE:
+      case SolverLanguagePackage.LOGIC_LITERAL__VALUE:
        return value != VALUE_EDEFAULT;
    }
    return super.eIsSet(featureID);
@@ -176,4 +177,4 @@ public class IntObjectImpl extends DataObjectImpl implements IntObject
    return result.toString();
  }
-} //IntObjectImpl
+} //LogicLiteralImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LowerBoundedScopeDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LowerBoundedScopeDefinitionImpl.java
new file mode 100644
index 00000000..5eb671f3
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/LowerBoundedScopeDefinitionImpl.java
@@ -0,0 +1,179 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.LowerBoundedScopeDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Lower Bounded Scope Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.LowerBoundedScopeDefinitionImpl#getLowerBound <em>Lower Bound</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class LowerBoundedScopeDefinitionImpl extends ScopeDefinitionImpl implements LowerBoundedScopeDefinition
+{
+  /**
+   * The default value of the '{@link #getLowerBound() <em>Lower Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLowerBound()
+   * @generated
+   * @ordered
+   */
+  protected static final int LOWER_BOUND_EDEFAULT = 0;
+  /**
+   * The cached value of the '{@link #getLowerBound() <em>Lower Bound</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getLowerBound()
+   * @generated
+   * @ordered
+   */
+  protected int lowerBound = LOWER_BOUND_EDEFAULT;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected LowerBoundedScopeDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.LOWER_BOUNDED_SCOPE_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public int getLowerBound()
+  {
+    return lowerBound;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setLowerBound(int newLowerBound)
+  {
+    int oldLowerBound = lowerBound;
+    lowerBound = newLowerBound;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.LOWER_BOUNDED_SCOPE_DEFINITION__LOWER_BOUND, oldLowerBound, lowerBound));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.LOWER_BOUNDED_SCOPE_DEFINITION__LOWER_BOUND:
+        return getLowerBound();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.LOWER_BOUNDED_SCOPE_DEFINITION__LOWER_BOUND:
+        setLowerBound((Integer)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.LOWER_BOUNDED_SCOPE_DEFINITION__LOWER_BOUND:
+        setLowerBound(LOWER_BOUND_EDEFAULT);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.LOWER_BOUNDED_SCOPE_DEFINITION__LOWER_BOUND:
+        return lowerBound != LOWER_BOUND_EDEFAULT;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (lowerBound: ");
+    result.append(lowerBound);
+    result.append(')');
+    return result.toString();
+  }
+} //LowerBoundedScopeDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AllObjectsImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ManyMultiplicityImpl.java
index b1e9c3d0..c248b4ea 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/AllObjectsImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ManyMultiplicityImpl.java
@@ -1,28 +1,28 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
 import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.AllObjects;
+import org.eclipse.viatra.solver.language.solverLanguage.ManyMultiplicity;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>All Objects</b></em>'.
+ * An implementation of the model object '<em><b>Many Multiplicity</b></em>'.
 * <!-- end-user-doc -->
 *
 * @generated
 */
-public class AllObjectsImpl extends ComplexObjectImpl implements AllObjects
+public class ManyMultiplicityImpl extends MultiplicityImpl implements ManyMultiplicity
 {
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected AllObjectsImpl()
+  protected ManyMultiplicityImpl()
  {
    super();
  }
@@ -35,7 +35,7 @@ public class AllObjectsImpl extends ComplexObjectImpl implements AllObjects
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.ALL_OBJECTS;
+    return SolverLanguagePackage.Literals.MANY_MULTIPLICITY;
  }
-} //AllObjectsImpl
+} //ManyMultiplicityImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MemberDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MemberDefinitionImpl.java
new file mode 100644
index 00000000..69021347
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MemberDefinitionImpl.java
@@ -0,0 +1,463 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.MemberDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.Multiplicity;
+import org.eclipse.viatra.solver.language.solverLanguage.NamedElement;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Member Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MemberDefinitionImpl#isContainment <em>Containment</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MemberDefinitionImpl#getType <em>Type</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MemberDefinitionImpl#getMultiplicity <em>Multiplicity</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MemberDefinitionImpl#getName <em>Name</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MemberDefinitionImpl#getOpposite <em>Opposite</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class MemberDefinitionImpl extends MinimalEObjectImpl.Container implements MemberDefinition
+{
+  /**
+   * The default value of the '{@link #isContainment() <em>Containment</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isContainment()
+   * @generated
+   * @ordered
+   */
+  protected static final boolean CONTAINMENT_EDEFAULT = false;
+  /**
+   * The cached value of the '{@link #isContainment() <em>Containment</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isContainment()
+   * @generated
+   * @ordered
+   */
+  protected boolean containment = CONTAINMENT_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getType() <em>Type</em>}' reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getType()
+   * @generated
+   * @ordered
+   */
+  protected NamedElement type;
+  /**
+   * The cached value of the '{@link #getMultiplicity() <em>Multiplicity</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getMultiplicity()
+   * @generated
+   * @ordered
+   */
+  protected Multiplicity multiplicity;
+  /**
+   * The default value of the '{@link #getName() <em>Name</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getName()
+   * @generated
+   * @ordered
+   */
+  protected static final String NAME_EDEFAULT = null;
+  /**
+   * The cached value of the '{@link #getName() <em>Name</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getName()
+   * @generated
+   * @ordered
+   */
+  protected String name = NAME_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getOpposite() <em>Opposite</em>}' reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOpposite()
+   * @generated
+   * @ordered
+   */
+  protected NamedElement opposite;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected MemberDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.MEMBER_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean isContainment()
+  {
+    return containment;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setContainment(boolean newContainment)
+  {
+    boolean oldContainment = containment;
+    containment = newContainment;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MEMBER_DEFINITION__CONTAINMENT, oldContainment, containment));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NamedElement getType()
+  {
+    if (type != null && type.eIsProxy())
+    {
+      InternalEObject oldType = (InternalEObject)type;
+      type = (NamedElement)eResolveProxy(oldType);
+      if (type != oldType)
+      {
+        if (eNotificationRequired())
+          eNotify(new ENotificationImpl(this, Notification.RESOLVE, SolverLanguagePackage.MEMBER_DEFINITION__TYPE, oldType, type));
+      }
+    }
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NamedElement basicGetType()
+  {
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setType(NamedElement newType)
+  {
+    NamedElement oldType = type;
+    type = newType;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MEMBER_DEFINITION__TYPE, oldType, type));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Multiplicity getMultiplicity()
+  {
+    return multiplicity;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetMultiplicity(Multiplicity newMultiplicity, NotificationChain msgs)
+  {
+    Multiplicity oldMultiplicity = multiplicity;
+    multiplicity = newMultiplicity;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY, oldMultiplicity, newMultiplicity);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setMultiplicity(Multiplicity newMultiplicity)
+  {
+    if (newMultiplicity != multiplicity)
+    {
+      NotificationChain msgs = null;
+      if (multiplicity != null)
+        msgs = ((InternalEObject)multiplicity).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY, null, msgs);
+      if (newMultiplicity != null)
+        msgs = ((InternalEObject)newMultiplicity).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY, null, msgs);
+      msgs = basicSetMultiplicity(newMultiplicity, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY, newMultiplicity, newMultiplicity));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String getName()
+  {
+    return name;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setName(String newName)
+  {
+    String oldName = name;
+    name = newName;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MEMBER_DEFINITION__NAME, oldName, name));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NamedElement getOpposite()
+  {
+    if (opposite != null && opposite.eIsProxy())
+    {
+      InternalEObject oldOpposite = (InternalEObject)opposite;
+      opposite = (NamedElement)eResolveProxy(oldOpposite);
+      if (opposite != oldOpposite)
+      {
+        if (eNotificationRequired())
+          eNotify(new ENotificationImpl(this, Notification.RESOLVE, SolverLanguagePackage.MEMBER_DEFINITION__OPPOSITE, oldOpposite, opposite));
+      }
+    }
+    return opposite;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NamedElement basicGetOpposite()
+  {
+    return opposite;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setOpposite(NamedElement newOpposite)
+  {
+    NamedElement oldOpposite = opposite;
+    opposite = newOpposite;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MEMBER_DEFINITION__OPPOSITE, oldOpposite, opposite));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY:
+        return basicSetMultiplicity(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.MEMBER_DEFINITION__CONTAINMENT:
+        return isContainment();
+      case SolverLanguagePackage.MEMBER_DEFINITION__TYPE:
+        if (resolve) return getType();
+        return basicGetType();
+      case SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY:
+        return getMultiplicity();
+      case SolverLanguagePackage.MEMBER_DEFINITION__NAME:
+        return getName();
+      case SolverLanguagePackage.MEMBER_DEFINITION__OPPOSITE:
+        if (resolve) return getOpposite();
+        return basicGetOpposite();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.MEMBER_DEFINITION__CONTAINMENT:
+        setContainment((Boolean)newValue);
+        return;
+      case SolverLanguagePackage.MEMBER_DEFINITION__TYPE:
+        setType((NamedElement)newValue);
+        return;
+      case SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY:
+        setMultiplicity((Multiplicity)newValue);
+        return;
+      case SolverLanguagePackage.MEMBER_DEFINITION__NAME:
+        setName((String)newValue);
+        return;
+      case SolverLanguagePackage.MEMBER_DEFINITION__OPPOSITE:
+        setOpposite((NamedElement)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.MEMBER_DEFINITION__CONTAINMENT:
+        setContainment(CONTAINMENT_EDEFAULT);
+        return;
+      case SolverLanguagePackage.MEMBER_DEFINITION__TYPE:
+        setType((NamedElement)null);
+        return;
+      case SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY:
+        setMultiplicity((Multiplicity)null);
+        return;
+      case SolverLanguagePackage.MEMBER_DEFINITION__NAME:
+        setName(NAME_EDEFAULT);
+        return;
+      case SolverLanguagePackage.MEMBER_DEFINITION__OPPOSITE:
+        setOpposite((NamedElement)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.MEMBER_DEFINITION__CONTAINMENT:
+        return containment != CONTAINMENT_EDEFAULT;
+      case SolverLanguagePackage.MEMBER_DEFINITION__TYPE:
+        return type != null;
+      case SolverLanguagePackage.MEMBER_DEFINITION__MULTIPLICITY:
+        return multiplicity != null;
+      case SolverLanguagePackage.MEMBER_DEFINITION__NAME:
+        return NAME_EDEFAULT == null ? name != null : !NAME_EDEFAULT.equals(name);
+      case SolverLanguagePackage.MEMBER_DEFINITION__OPPOSITE:
+        return opposite != null;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (containment: ");
+    result.append(containment);
+    result.append(", name: ");
+    result.append(name);
+    result.append(')');
+    return result.toString();
+  }
+} //MemberDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MetricDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MetricDefinitionImpl.java
new file mode 100644
index 00000000..8f84d2f1
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MetricDefinitionImpl.java
@@ -0,0 +1,343 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.MetricDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.MetricType;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Metric Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MetricDefinitionImpl#getHead <em>Head</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MetricDefinitionImpl#getBody <em>Body</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MetricDefinitionImpl#getType <em>Type</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class MetricDefinitionImpl extends StatementImpl implements MetricDefinition
+{
+  /**
+   * The cached value of the '{@link #getHead() <em>Head</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getHead()
+   * @generated
+   * @ordered
+   */
+  protected Expression head;
+  /**
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getBody()
+   * @generated
+   * @ordered
+   */
+  protected Expression body;
+  /**
+   * The default value of the '{@link #getType() <em>Type</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getType()
+   * @generated
+   * @ordered
+   */
+  protected static final MetricType TYPE_EDEFAULT = MetricType.INT;
+  /**
+   * The cached value of the '{@link #getType() <em>Type</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getType()
+   * @generated
+   * @ordered
+   */
+  protected MetricType type = TYPE_EDEFAULT;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected MetricDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.METRIC_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getHead()
+  {
+    return head;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetHead(Expression newHead, NotificationChain msgs)
+  {
+    Expression oldHead = head;
+    head = newHead;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.METRIC_DEFINITION__HEAD, oldHead, newHead);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setHead(Expression newHead)
+  {
+    if (newHead != head)
+    {
+      NotificationChain msgs = null;
+      if (head != null)
+        msgs = ((InternalEObject)head).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.METRIC_DEFINITION__HEAD, null, msgs);
+      if (newHead != null)
+        msgs = ((InternalEObject)newHead).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.METRIC_DEFINITION__HEAD, null, msgs);
+      msgs = basicSetHead(newHead, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.METRIC_DEFINITION__HEAD, newHead, newHead));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getBody()
+  {
+    return body;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
+  {
+    Expression oldBody = body;
+    body = newBody;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.METRIC_DEFINITION__BODY, oldBody, newBody);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setBody(Expression newBody)
+  {
+    if (newBody != body)
+    {
+      NotificationChain msgs = null;
+      if (body != null)
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.METRIC_DEFINITION__BODY, null, msgs);
+      if (newBody != null)
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.METRIC_DEFINITION__BODY, null, msgs);
+      msgs = basicSetBody(newBody, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.METRIC_DEFINITION__BODY, newBody, newBody));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public MetricType getType()
+  {
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setType(MetricType newType)
+  {
+    MetricType oldType = type;
+    type = newType == null ? TYPE_EDEFAULT : newType;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.METRIC_DEFINITION__TYPE, oldType, type));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.METRIC_DEFINITION__HEAD:
+        return basicSetHead(null, msgs);
+      case SolverLanguagePackage.METRIC_DEFINITION__BODY:
+        return basicSetBody(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.METRIC_DEFINITION__HEAD:
+        return getHead();
+      case SolverLanguagePackage.METRIC_DEFINITION__BODY:
+        return getBody();
+      case SolverLanguagePackage.METRIC_DEFINITION__TYPE:
+        return getType();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.METRIC_DEFINITION__HEAD:
+        setHead((Expression)newValue);
+        return;
+      case SolverLanguagePackage.METRIC_DEFINITION__BODY:
+        setBody((Expression)newValue);
+        return;
+      case SolverLanguagePackage.METRIC_DEFINITION__TYPE:
+        setType((MetricType)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.METRIC_DEFINITION__HEAD:
+        setHead((Expression)null);
+        return;
+      case SolverLanguagePackage.METRIC_DEFINITION__BODY:
+        setBody((Expression)null);
+        return;
+      case SolverLanguagePackage.METRIC_DEFINITION__TYPE:
+        setType(TYPE_EDEFAULT);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.METRIC_DEFINITION__HEAD:
+        return head != null;
+      case SolverLanguagePackage.METRIC_DEFINITION__BODY:
+        return body != null;
+      case SolverLanguagePackage.METRIC_DEFINITION__TYPE:
+        return type != TYPE_EDEFAULT;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (type: ");
+    result.append(type);
+    result.append(')');
+    return result.toString();
+  }
+} //MetricDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MultiplicityDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MultiplicityDefinitionImpl.java
deleted file mode 100644
index a346568c..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MultiplicityDefinitionImpl.java
+++ /dev/null
@@ -1,296 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.MultiplicityDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Multiplicity Definition</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MultiplicityDefinitionImpl#getLower <em>Lower</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MultiplicityDefinitionImpl#getUpper <em>Upper</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.MultiplicityDefinitionImpl#isUnlimitedUpper <em>Unlimited Upper</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class MultiplicityDefinitionImpl extends MinimalEObjectImpl.Container implements MultiplicityDefinition
-{
-  /**
-   * The default value of the '{@link #getLower() <em>Lower</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getLower()
-   * @generated
-   * @ordered
-   */
-  protected static final int LOWER_EDEFAULT = 0;
-  /**
-   * The cached value of the '{@link #getLower() <em>Lower</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getLower()
-   * @generated
-   * @ordered
-   */
-  protected int lower = LOWER_EDEFAULT;
-  /**
-   * The default value of the '{@link #getUpper() <em>Upper</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getUpper()
-   * @generated
-   * @ordered
-   */
-  protected static final int UPPER_EDEFAULT = 0;
-  /**
-   * The cached value of the '{@link #getUpper() <em>Upper</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getUpper()
-   * @generated
-   * @ordered
-   */
-  protected int upper = UPPER_EDEFAULT;
-  /**
-   * The default value of the '{@link #isUnlimitedUpper() <em>Unlimited Upper</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isUnlimitedUpper()
-   * @generated
-   * @ordered
-   */
-  protected static final boolean UNLIMITED_UPPER_EDEFAULT = false;
-  /**
-   * The cached value of the '{@link #isUnlimitedUpper() <em>Unlimited Upper</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isUnlimitedUpper()
-   * @generated
-   * @ordered
-   */
-  protected boolean unlimitedUpper = UNLIMITED_UPPER_EDEFAULT;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected MultiplicityDefinitionImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.MULTIPLICITY_DEFINITION;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public int getLower()
-  {
-    return lower;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setLower(int newLower)
-  {
-    int oldLower = lower;
-    lower = newLower;
-    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MULTIPLICITY_DEFINITION__LOWER, oldLower, lower));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public int getUpper()
-  {
-    return upper;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setUpper(int newUpper)
-  {
-    int oldUpper = upper;
-    upper = newUpper;
-    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MULTIPLICITY_DEFINITION__UPPER, oldUpper, upper));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean isUnlimitedUpper()
-  {
-    return unlimitedUpper;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setUnlimitedUpper(boolean newUnlimitedUpper)
-  {
-    boolean oldUnlimitedUpper = unlimitedUpper;
-    unlimitedUpper = newUnlimitedUpper;
-    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.MULTIPLICITY_DEFINITION__UNLIMITED_UPPER, oldUnlimitedUpper, unlimitedUpper));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__LOWER:
-        return getLower();
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__UPPER:
-        return getUpper();
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__UNLIMITED_UPPER:
-        return isUnlimitedUpper();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__LOWER:
-        setLower((Integer)newValue);
-        return;
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__UPPER:
-        setUpper((Integer)newValue);
-        return;
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__UNLIMITED_UPPER:
-        setUnlimitedUpper((Boolean)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__LOWER:
-        setLower(LOWER_EDEFAULT);
-        return;
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__UPPER:
-        setUpper(UPPER_EDEFAULT);
-        return;
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__UNLIMITED_UPPER:
-        setUnlimitedUpper(UNLIMITED_UPPER_EDEFAULT);
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__LOWER:
-        return lower != LOWER_EDEFAULT;
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__UPPER:
-        return upper != UPPER_EDEFAULT;
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION__UNLIMITED_UPPER:
-        return unlimitedUpper != UNLIMITED_UPPER_EDEFAULT;
-    }
-    return super.eIsSet(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public String toString()
-  {
-    if (eIsProxy()) return super.toString();
-    StringBuilder result = new StringBuilder(super.toString());
-    result.append(" (lower: ");
-    result.append(lower);
-    result.append(", upper: ");
-    result.append(upper);
-    result.append(", unlimitedUpper: ");
-    result.append(unlimitedUpper);
-    result.append(')');
-    return result.toString();
-  }
-} //MultiplicityDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ClosureTypeImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MultiplicityImpl.java
index 98136f79..935cf5be 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ClosureTypeImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/MultiplicityImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -7,24 +7,24 @@ import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.ClosureType;
+import org.eclipse.viatra.solver.language.solverLanguage.Multiplicity;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Closure Type</b></em>'.
+ * An implementation of the model object '<em><b>Multiplicity</b></em>'.
 * <!-- end-user-doc -->
 *
 * @generated
 */
-public class ClosureTypeImpl extends MinimalEObjectImpl.Container implements ClosureType
+public class MultiplicityImpl extends MinimalEObjectImpl.Container implements Multiplicity
 {
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected ClosureTypeImpl()
+  protected MultiplicityImpl()
  {
    super();
  }
@@ -37,7 +37,7 @@ public class ClosureTypeImpl extends MinimalEObjectImpl.Container implements Clo
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.CLOSURE_TYPE;
+    return SolverLanguagePackage.Literals.MULTIPLICITY;
  }
-} //ClosureTypeImpl
+} //MultiplicityImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/VariableImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/NamedElementImpl.java
index 9a254023..a94f9894 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/VariableImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/NamedElementImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -8,24 +8,25 @@ import org.eclipse.emf.common.notify.Notification;
 import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.NamedElement;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Variable;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Variable</b></em>'.
+ * An implementation of the model object '<em><b>Named Element</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.VariableImpl#getName <em>Name</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.NamedElementImpl#getName <em>Name</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class VariableImpl extends LiteralImpl implements Variable
+public class NamedElementImpl extends MinimalEObjectImpl.Container implements NamedElement
 {
  /**
   * The default value of the '{@link #getName() <em>Name</em>}' attribute.
@@ -52,7 +53,7 @@ public class VariableImpl extends LiteralImpl implements Variable
   * <!-- end-user-doc -->
   * @generated
   */
-  protected VariableImpl()
+  protected NamedElementImpl()
  {
    super();
  }
@@ -65,7 +66,7 @@ public class VariableImpl extends LiteralImpl implements Variable
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.VARIABLE;
+    return SolverLanguagePackage.Literals.NAMED_ELEMENT;
  }
  /**
@@ -90,7 +91,7 @@ public class VariableImpl extends LiteralImpl implements Variable
    String oldName = name;
    name = newName;
    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.VARIABLE__NAME, oldName, name));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.NAMED_ELEMENT__NAME, oldName, name));
  }
  /**
@@ -103,7 +104,7 @@ public class VariableImpl extends LiteralImpl implements Variable
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.VARIABLE__NAME:
+      case SolverLanguagePackage.NAMED_ELEMENT__NAME:
        return getName();
    }
    return super.eGet(featureID, resolve, coreType);
@@ -119,7 +120,7 @@ public class VariableImpl extends LiteralImpl implements Variable
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.VARIABLE__NAME:
+      case SolverLanguagePackage.NAMED_ELEMENT__NAME:
        setName((String)newValue);
        return;
    }
@@ -136,7 +137,7 @@ public class VariableImpl extends LiteralImpl implements Variable
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.VARIABLE__NAME:
+      case SolverLanguagePackage.NAMED_ELEMENT__NAME:
        setName(NAME_EDEFAULT);
        return;
    }
@@ -153,7 +154,7 @@ public class VariableImpl extends LiteralImpl implements Variable
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.VARIABLE__NAME:
+      case SolverLanguagePackage.NAMED_ELEMENT__NAME:
        return NAME_EDEFAULT == null ? name != null : !NAME_EDEFAULT.equals(name);
    }
    return super.eIsSet(featureID);
@@ -176,4 +177,4 @@ public class VariableImpl extends LiteralImpl implements Variable
    return result.toString();
  }
-} //VariableImpl
+} //NamedElementImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/RealObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/NumericLiteralImpl.java
index bc32a9a6..04622dfb 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/RealObjectImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/NumericLiteralImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -11,23 +11,23 @@ import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.RealObject;
+import org.eclipse.viatra.solver.language.solverLanguage.NumericLiteral;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Real Object</b></em>'.
+ * An implementation of the model object '<em><b>Numeric Literal</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.RealObjectImpl#getValue <em>Value</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.NumericLiteralImpl#getValue <em>Value</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class RealObjectImpl extends DataObjectImpl implements RealObject
+public class NumericLiteralImpl extends LiteralImpl implements NumericLiteral
 {
  /**
   * The default value of the '{@link #getValue() <em>Value</em>}' attribute.
@@ -54,7 +54,7 @@ public class RealObjectImpl extends DataObjectImpl implements RealObject
   * <!-- end-user-doc -->
   * @generated
   */
-  protected RealObjectImpl()
+  protected NumericLiteralImpl()
  {
    super();
  }
@@ -67,7 +67,7 @@ public class RealObjectImpl extends DataObjectImpl implements RealObject
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.REAL_OBJECT;
+    return SolverLanguagePackage.Literals.NUMERIC_LITERAL;
  }
  /**
@@ -92,7 +92,7 @@ public class RealObjectImpl extends DataObjectImpl implements RealObject
    BigDecimal oldValue = value;
    value = newValue;
    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.REAL_OBJECT__VALUE, oldValue, value));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.NUMERIC_LITERAL__VALUE, oldValue, value));
  }
  /**
@@ -105,7 +105,7 @@ public class RealObjectImpl extends DataObjectImpl implements RealObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.REAL_OBJECT__VALUE:
+      case SolverLanguagePackage.NUMERIC_LITERAL__VALUE:
        return getValue();
    }
    return super.eGet(featureID, resolve, coreType);
@@ -121,7 +121,7 @@ public class RealObjectImpl extends DataObjectImpl implements RealObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.REAL_OBJECT__VALUE:
+      case SolverLanguagePackage.NUMERIC_LITERAL__VALUE:
        setValue((BigDecimal)newValue);
        return;
    }
@@ -138,7 +138,7 @@ public class RealObjectImpl extends DataObjectImpl implements RealObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.REAL_OBJECT__VALUE:
+      case SolverLanguagePackage.NUMERIC_LITERAL__VALUE:
        setValue(VALUE_EDEFAULT);
        return;
    }
@@ -155,7 +155,7 @@ public class RealObjectImpl extends DataObjectImpl implements RealObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.REAL_OBJECT__VALUE:
+      case SolverLanguagePackage.NUMERIC_LITERAL__VALUE:
        return VALUE_EDEFAULT == null ? value != null : !VALUE_EDEFAULT.equals(value);
    }
    return super.eIsSet(featureID);
@@ -178,4 +178,4 @@ public class RealObjectImpl extends DataObjectImpl implements RealObject
    return result.toString();
  }
-} //RealObjectImpl
+} //NumericLiteralImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ObjectImpl.java
deleted file mode 100644
index d2f9b8d9..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ObjectImpl.java
+++ /dev/null
@@ -1,40 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Object</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class ObjectImpl extends ComplexObjectImpl implements org.eclipse.viatra.solver.language.solverLanguage.Object
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected ObjectImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.OBJECT;
-  }
-} //ObjectImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ObjectiveDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ObjectiveDefinitionImpl.java
new file mode 100644
index 00000000..43b16e31
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ObjectiveDefinitionImpl.java
@@ -0,0 +1,270 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.ObjectiveDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.ObjectiveKind;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Objective Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ObjectiveDefinitionImpl#getKind <em>Kind</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ObjectiveDefinitionImpl#getObjective <em>Objective</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class ObjectiveDefinitionImpl extends StatementImpl implements ObjectiveDefinition
+{
+  /**
+   * The default value of the '{@link #getKind() <em>Kind</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getKind()
+   * @generated
+   * @ordered
+   */
+  protected static final ObjectiveKind KIND_EDEFAULT = ObjectiveKind.MINIMIZE;
+  /**
+   * The cached value of the '{@link #getKind() <em>Kind</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getKind()
+   * @generated
+   * @ordered
+   */
+  protected ObjectiveKind kind = KIND_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getObjective() <em>Objective</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getObjective()
+   * @generated
+   * @ordered
+   */
+  protected Expression objective;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected ObjectiveDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.OBJECTIVE_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public ObjectiveKind getKind()
+  {
+    return kind;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setKind(ObjectiveKind newKind)
+  {
+    ObjectiveKind oldKind = kind;
+    kind = newKind == null ? KIND_EDEFAULT : newKind;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.OBJECTIVE_DEFINITION__KIND, oldKind, kind));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getObjective()
+  {
+    return objective;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetObjective(Expression newObjective, NotificationChain msgs)
+  {
+    Expression oldObjective = objective;
+    objective = newObjective;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE, oldObjective, newObjective);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setObjective(Expression newObjective)
+  {
+    if (newObjective != objective)
+    {
+      NotificationChain msgs = null;
+      if (objective != null)
+        msgs = ((InternalEObject)objective).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE, null, msgs);
+      if (newObjective != null)
+        msgs = ((InternalEObject)newObjective).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE, null, msgs);
+      msgs = basicSetObjective(newObjective, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE, newObjective, newObjective));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE:
+        return basicSetObjective(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__KIND:
+        return getKind();
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE:
+        return getObjective();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__KIND:
+        setKind((ObjectiveKind)newValue);
+        return;
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE:
+        setObjective((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__KIND:
+        setKind(KIND_EDEFAULT);
+        return;
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE:
+        setObjective((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__KIND:
+        return kind != KIND_EDEFAULT;
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION__OBJECTIVE:
+        return objective != null;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (kind: ");
+    result.append(kind);
+    result.append(')');
+    return result.toString();
+  }
+} //ObjectiveDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PartialitySymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PartialitySymbolImpl.java
deleted file mode 100644
index efc2c5f5..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PartialitySymbolImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.PartialitySymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Partiality Symbol</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class PartialitySymbolImpl extends SymbolImpl implements PartialitySymbol
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected PartialitySymbolImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.PARTIALITY_SYMBOL;
-  }
-} //PartialitySymbolImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PositiveImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PositiveImpl.java
deleted file mode 100644
index 130cfe7a..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PositiveImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.Positive;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Positive</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class PositiveImpl extends PolarityImpl implements Positive
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected PositiveImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.POSITIVE;
-  }
-} //PositiveImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PredicateDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PredicateDefinitionImpl.java
new file mode 100644
index 00000000..50130f01
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PredicateDefinitionImpl.java
@@ -0,0 +1,400 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.PredicateDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Predicate Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PredicateDefinitionImpl#getHead <em>Head</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PredicateDefinitionImpl#getBody <em>Body</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PredicateDefinitionImpl#isFunctional <em>Functional</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PredicateDefinitionImpl#isError <em>Error</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class PredicateDefinitionImpl extends StatementImpl implements PredicateDefinition
+{
+  /**
+   * The cached value of the '{@link #getHead() <em>Head</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getHead()
+   * @generated
+   * @ordered
+   */
+  protected Expression head;
+  /**
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getBody()
+   * @generated
+   * @ordered
+   */
+  protected Expression body;
+  /**
+   * The default value of the '{@link #isFunctional() <em>Functional</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isFunctional()
+   * @generated
+   * @ordered
+   */
+  protected static final boolean FUNCTIONAL_EDEFAULT = false;
+  /**
+   * The cached value of the '{@link #isFunctional() <em>Functional</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isFunctional()
+   * @generated
+   * @ordered
+   */
+  protected boolean functional = FUNCTIONAL_EDEFAULT;
+  /**
+   * The default value of the '{@link #isError() <em>Error</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isError()
+   * @generated
+   * @ordered
+   */
+  protected static final boolean ERROR_EDEFAULT = false;
+  /**
+   * The cached value of the '{@link #isError() <em>Error</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isError()
+   * @generated
+   * @ordered
+   */
+  protected boolean error = ERROR_EDEFAULT;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected PredicateDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.PREDICATE_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getHead()
+  {
+    return head;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetHead(Expression newHead, NotificationChain msgs)
+  {
+    Expression oldHead = head;
+    head = newHead;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE_DEFINITION__HEAD, oldHead, newHead);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setHead(Expression newHead)
+  {
+    if (newHead != head)
+    {
+      NotificationChain msgs = null;
+      if (head != null)
+        msgs = ((InternalEObject)head).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PREDICATE_DEFINITION__HEAD, null, msgs);
+      if (newHead != null)
+        msgs = ((InternalEObject)newHead).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PREDICATE_DEFINITION__HEAD, null, msgs);
+      msgs = basicSetHead(newHead, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE_DEFINITION__HEAD, newHead, newHead));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getBody()
+  {
+    return body;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
+  {
+    Expression oldBody = body;
+    body = newBody;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE_DEFINITION__BODY, oldBody, newBody);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setBody(Expression newBody)
+  {
+    if (newBody != body)
+    {
+      NotificationChain msgs = null;
+      if (body != null)
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PREDICATE_DEFINITION__BODY, null, msgs);
+      if (newBody != null)
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PREDICATE_DEFINITION__BODY, null, msgs);
+      msgs = basicSetBody(newBody, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE_DEFINITION__BODY, newBody, newBody));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean isFunctional()
+  {
+    return functional;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setFunctional(boolean newFunctional)
+  {
+    boolean oldFunctional = functional;
+    functional = newFunctional;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE_DEFINITION__FUNCTIONAL, oldFunctional, functional));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean isError()
+  {
+    return error;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setError(boolean newError)
+  {
+    boolean oldError = error;
+    error = newError;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE_DEFINITION__ERROR, oldError, error));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.PREDICATE_DEFINITION__HEAD:
+        return basicSetHead(null, msgs);
+      case SolverLanguagePackage.PREDICATE_DEFINITION__BODY:
+        return basicSetBody(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.PREDICATE_DEFINITION__HEAD:
+        return getHead();
+      case SolverLanguagePackage.PREDICATE_DEFINITION__BODY:
+        return getBody();
+      case SolverLanguagePackage.PREDICATE_DEFINITION__FUNCTIONAL:
+        return isFunctional();
+      case SolverLanguagePackage.PREDICATE_DEFINITION__ERROR:
+        return isError();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.PREDICATE_DEFINITION__HEAD:
+        setHead((Expression)newValue);
+        return;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__BODY:
+        setBody((Expression)newValue);
+        return;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__FUNCTIONAL:
+        setFunctional((Boolean)newValue);
+        return;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__ERROR:
+        setError((Boolean)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.PREDICATE_DEFINITION__HEAD:
+        setHead((Expression)null);
+        return;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__BODY:
+        setBody((Expression)null);
+        return;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__FUNCTIONAL:
+        setFunctional(FUNCTIONAL_EDEFAULT);
+        return;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__ERROR:
+        setError(ERROR_EDEFAULT);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.PREDICATE_DEFINITION__HEAD:
+        return head != null;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__BODY:
+        return body != null;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__FUNCTIONAL:
+        return functional != FUNCTIONAL_EDEFAULT;
+      case SolverLanguagePackage.PREDICATE_DEFINITION__ERROR:
+        return error != ERROR_EDEFAULT;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (functional: ");
+    result.append(functional);
+    result.append(", error: ");
+    result.append(error);
+    result.append(')');
+    return result.toString();
+  }
+} //PredicateDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PredicateImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PredicateImpl.java
deleted file mode 100644
index d3c7366d..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/PredicateImpl.java
+++ /dev/null
@@ -1,357 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import java.util.Collection;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.common.notify.NotificationChain;
-import org.eclipse.emf.common.util.EList;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.InternalEObject;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.util.EObjectContainmentEList;
-import org.eclipse.emf.ecore.util.InternalEList;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.Parameter;
-import org.eclipse.viatra.solver.language.solverLanguage.PatternBody;
-import org.eclipse.viatra.solver.language.solverLanguage.Predicate;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Predicate</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PredicateImpl#isIsError <em>Is Error</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PredicateImpl#getSymbol <em>Symbol</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PredicateImpl#getParameters <em>Parameters</em>}</li>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.PredicateImpl#getBodies <em>Bodies</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class PredicateImpl extends StatementImpl implements Predicate
-{
-  /**
-   * The default value of the '{@link #isIsError() <em>Is Error</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isIsError()
-   * @generated
-   * @ordered
-   */
-  protected static final boolean IS_ERROR_EDEFAULT = false;
-  /**
-   * The cached value of the '{@link #isIsError() <em>Is Error</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #isIsError()
-   * @generated
-   * @ordered
-   */
-  protected boolean isError = IS_ERROR_EDEFAULT;
-  /**
-   * The cached value of the '{@link #getSymbol() <em>Symbol</em>}' containment reference.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getSymbol()
-   * @generated
-   * @ordered
-   */
-  protected ModelSymbol symbol;
-  /**
-   * The cached value of the '{@link #getParameters() <em>Parameters</em>}' containment reference list.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getParameters()
-   * @generated
-   * @ordered
-   */
-  protected EList<Parameter> parameters;
-  /**
-   * The cached value of the '{@link #getBodies() <em>Bodies</em>}' containment reference list.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getBodies()
-   * @generated
-   * @ordered
-   */
-  protected EList<PatternBody> bodies;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected PredicateImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.PREDICATE;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean isIsError()
-  {
-    return isError;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setIsError(boolean newIsError)
-  {
-    boolean oldIsError = isError;
-    isError = newIsError;
-    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE__IS_ERROR, oldIsError, isError));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public ModelSymbol getSymbol()
-  {
-    return symbol;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  public NotificationChain basicSetSymbol(ModelSymbol newSymbol, NotificationChain msgs)
-  {
-    ModelSymbol oldSymbol = symbol;
-    symbol = newSymbol;
-    if (eNotificationRequired())
-    {
-      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE__SYMBOL, oldSymbol, newSymbol);
-      if (msgs == null) msgs = notification; else msgs.add(notification);
-    }
-    return msgs;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setSymbol(ModelSymbol newSymbol)
-  {
-    if (newSymbol != symbol)
-    {
-      NotificationChain msgs = null;
-      if (symbol != null)
-        msgs = ((InternalEObject)symbol).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PREDICATE__SYMBOL, null, msgs);
-      if (newSymbol != null)
-        msgs = ((InternalEObject)newSymbol).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.PREDICATE__SYMBOL, null, msgs);
-      msgs = basicSetSymbol(newSymbol, msgs);
-      if (msgs != null) msgs.dispatch();
-    }
-    else if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.PREDICATE__SYMBOL, newSymbol, newSymbol));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public EList<Parameter> getParameters()
-  {
-    if (parameters == null)
-    {
-      parameters = new EObjectContainmentEList<Parameter>(Parameter.class, this, SolverLanguagePackage.PREDICATE__PARAMETERS);
-    }
-    return parameters;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public EList<PatternBody> getBodies()
-  {
-    if (bodies == null)
-    {
-      bodies = new EObjectContainmentEList<PatternBody>(PatternBody.class, this, SolverLanguagePackage.PREDICATE__BODIES);
-    }
-    return bodies;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.PREDICATE__SYMBOL:
-        return basicSetSymbol(null, msgs);
-      case SolverLanguagePackage.PREDICATE__PARAMETERS:
-        return ((InternalEList<?>)getParameters()).basicRemove(otherEnd, msgs);
-      case SolverLanguagePackage.PREDICATE__BODIES:
-        return ((InternalEList<?>)getBodies()).basicRemove(otherEnd, msgs);
-    }
-    return super.eInverseRemove(otherEnd, featureID, msgs);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.PREDICATE__IS_ERROR:
-        return isIsError();
-      case SolverLanguagePackage.PREDICATE__SYMBOL:
-        return getSymbol();
-      case SolverLanguagePackage.PREDICATE__PARAMETERS:
-        return getParameters();
-      case SolverLanguagePackage.PREDICATE__BODIES:
-        return getBodies();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @SuppressWarnings("unchecked")
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.PREDICATE__IS_ERROR:
-        setIsError((Boolean)newValue);
-        return;
-      case SolverLanguagePackage.PREDICATE__SYMBOL:
-        setSymbol((ModelSymbol)newValue);
-        return;
-      case SolverLanguagePackage.PREDICATE__PARAMETERS:
-        getParameters().clear();
-        getParameters().addAll((Collection<? extends Parameter>)newValue);
-        return;
-      case SolverLanguagePackage.PREDICATE__BODIES:
-        getBodies().clear();
-        getBodies().addAll((Collection<? extends PatternBody>)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.PREDICATE__IS_ERROR:
-        setIsError(IS_ERROR_EDEFAULT);
-        return;
-      case SolverLanguagePackage.PREDICATE__SYMBOL:
-        setSymbol((ModelSymbol)null);
-        return;
-      case SolverLanguagePackage.PREDICATE__PARAMETERS:
-        getParameters().clear();
-        return;
-      case SolverLanguagePackage.PREDICATE__BODIES:
-        getBodies().clear();
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.PREDICATE__IS_ERROR:
-        return isError != IS_ERROR_EDEFAULT;
-      case SolverLanguagePackage.PREDICATE__SYMBOL:
-        return symbol != null;
-      case SolverLanguagePackage.PREDICATE__PARAMETERS:
-        return parameters != null && !parameters.isEmpty();
-      case SolverLanguagePackage.PREDICATE__BODIES:
-        return bodies != null && !bodies.isEmpty();
-    }
-    return super.eIsSet(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public String toString()
-  {
-    if (eIsProxy()) return super.toString();
-    StringBuilder result = new StringBuilder(super.toString());
-    result.append(" (isError: ");
-    result.append(isError);
-    result.append(')');
-    return result.toString();
-  }
-} //PredicateImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ProblemImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ProblemImpl.java
index e5cc3585..744e604d 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ProblemImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ProblemImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/RealSymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/RealSymbolImpl.java
deleted file mode 100644
index 8cfd0980..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/RealSymbolImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.RealSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Real Symbol</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class RealSymbolImpl extends DataSymbolImpl implements RealSymbol
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected RealSymbolImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.REAL_SYMBOL;
-  }
-} //RealSymbolImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ReferenceImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ReferenceImpl.java
new file mode 100644
index 00000000..be44c0e9
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ReferenceImpl.java
@@ -0,0 +1,175 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.NamedElement;
+import org.eclipse.viatra.solver.language.solverLanguage.Reference;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Reference</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ReferenceImpl#getReferred <em>Referred</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class ReferenceImpl extends ExpressionImpl implements Reference
+{
+  /**
+   * The cached value of the '{@link #getReferred() <em>Referred</em>}' reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getReferred()
+   * @generated
+   * @ordered
+   */
+  protected NamedElement referred;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected ReferenceImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.REFERENCE;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NamedElement getReferred()
+  {
+    if (referred != null && referred.eIsProxy())
+    {
+      InternalEObject oldReferred = (InternalEObject)referred;
+      referred = (NamedElement)eResolveProxy(oldReferred);
+      if (referred != oldReferred)
+      {
+        if (eNotificationRequired())
+          eNotify(new ENotificationImpl(this, Notification.RESOLVE, SolverLanguagePackage.REFERENCE__REFERRED, oldReferred, referred));
+      }
+    }
+    return referred;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NamedElement basicGetReferred()
+  {
+    return referred;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setReferred(NamedElement newReferred)
+  {
+    NamedElement oldReferred = referred;
+    referred = newReferred;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.REFERENCE__REFERRED, oldReferred, referred));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.REFERENCE__REFERRED:
+        if (resolve) return getReferred();
+        return basicGetReferred();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.REFERENCE__REFERRED:
+        setReferred((NamedElement)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.REFERENCE__REFERRED:
+        setReferred((NamedElement)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.REFERENCE__REFERRED:
+        return referred != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //ReferenceImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ReflexiveClosureImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ReflexiveClosureImpl.java
deleted file mode 100644
index 111b48cb..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ReflexiveClosureImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.ReflexiveClosure;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Reflexive Closure</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class ReflexiveClosureImpl extends ClosureTypeImpl implements ReflexiveClosure
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected ReflexiveClosureImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.REFLEXIVE_CLOSURE;
-  }
-} //ReflexiveClosureImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ScopeDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ScopeDefinitionImpl.java
new file mode 100644
index 00000000..be109307
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/ScopeDefinitionImpl.java
@@ -0,0 +1,175 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.NamedElement;
+import org.eclipse.viatra.solver.language.solverLanguage.ScopeDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Scope Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.ScopeDefinitionImpl#getType <em>Type</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class ScopeDefinitionImpl extends StatementImpl implements ScopeDefinition
+{
+  /**
+   * The cached value of the '{@link #getType() <em>Type</em>}' reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getType()
+   * @generated
+   * @ordered
+   */
+  protected NamedElement type;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected ScopeDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.SCOPE_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NamedElement getType()
+  {
+    if (type != null && type.eIsProxy())
+    {
+      InternalEObject oldType = (InternalEObject)type;
+      type = (NamedElement)eResolveProxy(oldType);
+      if (type != oldType)
+      {
+        if (eNotificationRequired())
+          eNotify(new ENotificationImpl(this, Notification.RESOLVE, SolverLanguagePackage.SCOPE_DEFINITION__TYPE, oldType, type));
+      }
+    }
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NamedElement basicGetType()
+  {
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setType(NamedElement newType)
+  {
+    NamedElement oldType = type;
+    type = newType;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.SCOPE_DEFINITION__TYPE, oldType, type));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SCOPE_DEFINITION__TYPE:
+        if (resolve) return getType();
+        return basicGetType();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SCOPE_DEFINITION__TYPE:
+        setType((NamedElement)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SCOPE_DEFINITION__TYPE:
+        setType((NamedElement)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SCOPE_DEFINITION__TYPE:
+        return type != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //ScopeDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SolverLanguageFactoryImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SolverLanguageFactoryImpl.java
index 5cb1dcdc..8a5976c2 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SolverLanguageFactoryImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SolverLanguageFactoryImpl.java
@@ -1,9 +1,10 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
 import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.EDataType;
 import org.eclipse.emf.ecore.EObject;
 import org.eclipse.emf.ecore.EPackage;
@@ -11,58 +12,7 @@ import org.eclipse.emf.ecore.impl.EFactoryImpl;
 import org.eclipse.emf.ecore.plugin.EcorePlugin;
-import org.eclipse.viatra.solver.language.solverLanguage.AllInstances;
+import org.eclipse.viatra.solver.language.solverLanguage.*;
-import org.eclipse.viatra.solver.language.solverLanguage.AllObjects;
-import org.eclipse.viatra.solver.language.solverLanguage.BasicInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanFalse;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanObject;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanTrue;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanValue;
-import org.eclipse.viatra.solver.language.solverLanguage.CDInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.ClassInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.ClosureType;
-import org.eclipse.viatra.solver.language.solverLanguage.ComplexObject;
-import org.eclipse.viatra.solver.language.solverLanguage.Constraint;
-import org.eclipse.viatra.solver.language.solverLanguage.DataObject;
-import org.eclipse.viatra.solver.language.solverLanguage.DataSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.DefaultInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.EnumInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.EqualsSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.ExistSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.False;
-import org.eclipse.viatra.solver.language.solverLanguage.FieldRelationInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.GlobalRelationInterpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.IntObject;
-import org.eclipse.viatra.solver.language.solverLanguage.IntegerSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.Interpretation;
-import org.eclipse.viatra.solver.language.solverLanguage.IrreflexiveClosure;
-import org.eclipse.viatra.solver.language.solverLanguage.Literal;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.MultiplicityDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.NamedObject;
-import org.eclipse.viatra.solver.language.solverLanguage.Negative;
-import org.eclipse.viatra.solver.language.solverLanguage.Parameter;
-import org.eclipse.viatra.solver.language.solverLanguage.PartialitySymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.PatternBody;
-import org.eclipse.viatra.solver.language.solverLanguage.Polarity;
-import org.eclipse.viatra.solver.language.solverLanguage.Positive;
-import org.eclipse.viatra.solver.language.solverLanguage.Predicate;
-import org.eclipse.viatra.solver.language.solverLanguage.Problem;
-import org.eclipse.viatra.solver.language.solverLanguage.RealObject;
-import org.eclipse.viatra.solver.language.solverLanguage.RealSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.ReflexiveClosure;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguageFactory;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Statement;
-import org.eclipse.viatra.solver.language.solverLanguage.StringObject;
-import org.eclipse.viatra.solver.language.solverLanguage.StringSymbol;
-import org.eclipse.viatra.solver.language.solverLanguage.Symbol;
-import org.eclipse.viatra.solver.language.solverLanguage.True;
-import org.eclipse.viatra.solver.language.solverLanguage.TruthValue;
-import org.eclipse.viatra.solver.language.solverLanguage.Unknown;
-import org.eclipse.viatra.solver.language.solverLanguage.UnnamedObject;
-import org.eclipse.viatra.solver.language.solverLanguage.Variable;
 /**
 * <!-- begin-user-doc -->
@@ -118,56 +68,50 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
    {
      case SolverLanguagePackage.PROBLEM: return createProblem();
      case SolverLanguagePackage.STATEMENT: return createStatement();
-      case SolverLanguagePackage.BOOLEAN_VALUE: return createBooleanValue();
+      case SolverLanguagePackage.PREDICATE_DEFINITION: return createPredicateDefinition();
-      case SolverLanguagePackage.TRUTH_VALUE: return createTruthValue();
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION: return createUnnamedErrorPrediateDefinition();
-      case SolverLanguagePackage.INTERPRETATION: return createInterpretation();
+      case SolverLanguagePackage.DEFAULT_DEFINITION: return createDefaultDefinition();
-      case SolverLanguagePackage.BASIC_INTERPRETATION: return createBasicInterpretation();
+      case SolverLanguagePackage.EXTERN_PREDICATE_DEFINITION: return createExternPredicateDefinition();
-      case SolverLanguagePackage.SYMBOL: return createSymbol();
+      case SolverLanguagePackage.METRIC_DEFINITION: return createMetricDefinition();
-      case SolverLanguagePackage.MODEL_SYMBOL: return createModelSymbol();
+      case SolverLanguagePackage.EXTERN_METRIC_DEFINITION: return createExternMetricDefinition();
-      case SolverLanguagePackage.PARTIALITY_SYMBOL: return createPartialitySymbol();
+      case SolverLanguagePackage.EXPRESSION: return createExpression();
-      case SolverLanguagePackage.EXIST_SYMBOL: return createExistSymbol();
+      case SolverLanguagePackage.IF_ELSE: return createIfElse();
-      case SolverLanguagePackage.EQUALS_SYMBOL: return createEqualsSymbol();
+      case SolverLanguagePackage.CASE: return createCase();
-      case SolverLanguagePackage.DATA_SYMBOL: return createDataSymbol();
+      case SolverLanguagePackage.COUNT: return createCount();
-      case SolverLanguagePackage.BOOLEAN_SYMBOL: return createBooleanSymbol();
+      case SolverLanguagePackage.AGGREGATION: return createAggregation();
-      case SolverLanguagePackage.INTEGER_SYMBOL: return createIntegerSymbol();
+      case SolverLanguagePackage.CALL: return createCall();
-      case SolverLanguagePackage.REAL_SYMBOL: return createRealSymbol();
+      case SolverLanguagePackage.ARGUMENT_LIST: return createArgumentList();
-      case SolverLanguagePackage.STRING_SYMBOL: return createStringSymbol();
+      case SolverLanguagePackage.ARGUMENT: return createArgument();
-      case SolverLanguagePackage.COMPLEX_OBJECT: return createComplexObject();
+      case SolverLanguagePackage.EXPRESSION_ARGUMENT: return createExpressionArgument();
-      case SolverLanguagePackage.OBJECT: return createObject();
+      case SolverLanguagePackage.STAR_ARGUMENT: return createStarArgument();
-      case SolverLanguagePackage.NAMED_OBJECT: return createNamedObject();
+      case SolverLanguagePackage.TYPED_ARGUMENT: return createTypedArgument();
-      case SolverLanguagePackage.UNNAMED_OBJECT: return createUnnamedObject();
+      case SolverLanguagePackage.TYPED_STAR_ARGUMENT: return createTypedStarArgument();
-      case SolverLanguagePackage.DATA_OBJECT: return createDataObject();
+      case SolverLanguagePackage.REFERENCE: return createReference();
-      case SolverLanguagePackage.BOOLEAN_OBJECT: return createBooleanObject();
+      case SolverLanguagePackage.INTERVAL: return createInterval();
-      case SolverLanguagePackage.INT_OBJECT: return createIntObject();
-      case SolverLanguagePackage.REAL_OBJECT: return createRealObject();
-      case SolverLanguagePackage.STRING_OBJECT: return createStringObject();
-      case SolverLanguagePackage.PREDICATE: return createPredicate();
-      case SolverLanguagePackage.PARAMETER: return createParameter();
-      case SolverLanguagePackage.PATTERN_BODY: return createPatternBody();
-      case SolverLanguagePackage.POLARITY: return createPolarity();
-      case SolverLanguagePackage.CONSTRAINT: return createConstraint();
-      case SolverLanguagePackage.CLOSURE_TYPE: return createClosureType();
      case SolverLanguagePackage.LITERAL: return createLiteral();
-      case SolverLanguagePackage.VARIABLE: return createVariable();
+      case SolverLanguagePackage.LOGIC_LITERAL: return createLogicLiteral();
-      case SolverLanguagePackage.ALL_INSTANCES: return createAllInstances();
+      case SolverLanguagePackage.NUMERIC_LITERAL: return createNumericLiteral();
-      case SolverLanguagePackage.ALL_OBJECTS: return createAllObjects();
+      case SolverLanguagePackage.INFINITY_LITERAL: return createInfinityLiteral();
-      case SolverLanguagePackage.DEFAULT_INTERPRETATION: return createDefaultInterpretation();
+      case SolverLanguagePackage.EMPTY_INTERVAL_LITERAL: return createEmptyIntervalLiteral();
-      case SolverLanguagePackage.CD_INTERPRETATION: return createCDInterpretation();
+      case SolverLanguagePackage.STRING_LITERAL: return createStringLiteral();
-      case SolverLanguagePackage.CLASS_INTERPRETATION: return createClassInterpretation();
+      case SolverLanguagePackage.MEMBER_DEFINITION: return createMemberDefinition();
-      case SolverLanguagePackage.ENUM_INTERPRETATION: return createEnumInterpretation();
+      case SolverLanguagePackage.MULTIPLICITY: return createMultiplicity();
-      case SolverLanguagePackage.FIELD_RELATION_INTERPRETATION: return createFieldRelationInterpretation();
+      case SolverLanguagePackage.MANY_MULTIPLICITY: return createManyMultiplicity();
-      case SolverLanguagePackage.GLOBAL_RELATION_INTERPRETATION: return createGlobalRelationInterpretation();
+      case SolverLanguagePackage.EXACT_MULTIPLICITY: return createExactMultiplicity();
-      case SolverLanguagePackage.MULTIPLICITY_DEFINITION: return createMultiplicityDefinition();
+      case SolverLanguagePackage.BOUNDED_MULTIPLICITY: return createBoundedMultiplicity();
-      case SolverLanguagePackage.BOOLEAN_TRUE: return createBooleanTrue();
+      case SolverLanguagePackage.SCOPE_DEFINITION: return createScopeDefinition();
-      case SolverLanguagePackage.BOOLEAN_FALSE: return createBooleanFalse();
+      case SolverLanguagePackage.EXACT_SCOPE_DEFINITION: return createExactScopeDefinition();
-      case SolverLanguagePackage.TRUE: return createTrue();
+      case SolverLanguagePackage.BOUNDED_SCOPE_DEFINITION: return createBoundedScopeDefinition();
-      case SolverLanguagePackage.FALSE: return createFalse();
+      case SolverLanguagePackage.LOWER_BOUNDED_SCOPE_DEFINITION: return createLowerBoundedScopeDefinition();
-      case SolverLanguagePackage.UNKNOWN: return createUnknown();
+      case SolverLanguagePackage.OBJECTIVE_DEFINITION: return createObjectiveDefinition();
-      case SolverLanguagePackage.ERROR: return createError();
+      case SolverLanguagePackage.NAMED_ELEMENT: return createNamedElement();
-      case SolverLanguagePackage.POSITIVE: return createPositive();
+      case SolverLanguagePackage.ASSERTION: return createAssertion();
-      case SolverLanguagePackage.NEGATIVE: return createNegative();
+      case SolverLanguagePackage.DISJUNCTION: return createDisjunction();
-      case SolverLanguagePackage.REFLEXIVE_CLOSURE: return createReflexiveClosure();
+      case SolverLanguagePackage.SWITCH: return createSwitch();
-      case SolverLanguagePackage.IRREFLEXIVE_CLOSURE: return createIrreflexiveClosure();
+      case SolverLanguagePackage.CONJUNCTION: return createConjunction();
+      case SolverLanguagePackage.COMPARISON: return createComparison();
+      case SolverLanguagePackage.BINARY_EXPRESSION: return createBinaryExpression();
+      case SolverLanguagePackage.UNARY_EXPRESSION: return createUnaryExpression();
      default:
        throw new IllegalArgumentException("The class '" + eClass.getName() + "' is not a valid classifier");
    }
@@ -179,6 +123,60 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
+  public Object createFromString(EDataType eDataType, String initialValue)
+  {
+    switch (eDataType.getClassifierID())
+    {
+      case SolverLanguagePackage.METRIC_TYPE:
+        return createMetricTypeFromString(eDataType, initialValue);
+      case SolverLanguagePackage.BINARY_OPERATOR:
+        return createBinaryOperatorFromString(eDataType, initialValue);
+      case SolverLanguagePackage.UNARY_OP:
+        return createUnaryOpFromString(eDataType, initialValue);
+      case SolverLanguagePackage.AGGREGATION_OP:
+        return createAggregationOpFromString(eDataType, initialValue);
+      case SolverLanguagePackage.LOGIC_VALUE:
+        return createLogicValueFromString(eDataType, initialValue);
+      case SolverLanguagePackage.OBJECTIVE_KIND:
+        return createObjectiveKindFromString(eDataType, initialValue);
+      default:
+        throw new IllegalArgumentException("The datatype '" + eDataType.getName() + "' is not a valid classifier");
+    }
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String convertToString(EDataType eDataType, Object instanceValue)
+  {
+    switch (eDataType.getClassifierID())
+    {
+      case SolverLanguagePackage.METRIC_TYPE:
+        return convertMetricTypeToString(eDataType, instanceValue);
+      case SolverLanguagePackage.BINARY_OPERATOR:
+        return convertBinaryOperatorToString(eDataType, instanceValue);
+      case SolverLanguagePackage.UNARY_OP:
+        return convertUnaryOpToString(eDataType, instanceValue);
+      case SolverLanguagePackage.AGGREGATION_OP:
+        return convertAggregationOpToString(eDataType, instanceValue);
+      case SolverLanguagePackage.LOGIC_VALUE:
+        return convertLogicValueToString(eDataType, instanceValue);
+      case SolverLanguagePackage.OBJECTIVE_KIND:
+        return convertObjectiveKindToString(eDataType, instanceValue);
+      default:
+        throw new IllegalArgumentException("The datatype '" + eDataType.getName() + "' is not a valid classifier");
+    }
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
  public Problem createProblem()
  {
    ProblemImpl problem = new ProblemImpl();
@@ -203,10 +201,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public BooleanValue createBooleanValue()
+  public PredicateDefinition createPredicateDefinition()
  {
-    BooleanValueImpl booleanValue = new BooleanValueImpl();
+    PredicateDefinitionImpl predicateDefinition = new PredicateDefinitionImpl();
-    return booleanValue;
+    return predicateDefinition;
  }
  /**
@@ -215,10 +213,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public TruthValue createTruthValue()
+  public UnnamedErrorPrediateDefinition createUnnamedErrorPrediateDefinition()
  {
-    TruthValueImpl truthValue = new TruthValueImpl();
+    UnnamedErrorPrediateDefinitionImpl unnamedErrorPrediateDefinition = new UnnamedErrorPrediateDefinitionImpl();
-    return truthValue;
+    return unnamedErrorPrediateDefinition;
  }
  /**
@@ -227,10 +225,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public Interpretation createInterpretation()
+  public DefaultDefinition createDefaultDefinition()
  {
-    InterpretationImpl interpretation = new InterpretationImpl();
+    DefaultDefinitionImpl defaultDefinition = new DefaultDefinitionImpl();
-    return interpretation;
+    return defaultDefinition;
  }
  /**
@@ -239,10 +237,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public BasicInterpretation createBasicInterpretation()
+  public ExternPredicateDefinition createExternPredicateDefinition()
  {
-    BasicInterpretationImpl basicInterpretation = new BasicInterpretationImpl();
+    ExternPredicateDefinitionImpl externPredicateDefinition = new ExternPredicateDefinitionImpl();
-    return basicInterpretation;
+    return externPredicateDefinition;
  }
  /**
@@ -251,10 +249,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public Symbol createSymbol()
+  public MetricDefinition createMetricDefinition()
  {
-    SymbolImpl symbol = new SymbolImpl();
+    MetricDefinitionImpl metricDefinition = new MetricDefinitionImpl();
-    return symbol;
+    return metricDefinition;
  }
  /**
@@ -263,10 +261,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public ModelSymbol createModelSymbol()
+  public ExternMetricDefinition createExternMetricDefinition()
  {
-    ModelSymbolImpl modelSymbol = new ModelSymbolImpl();
+    ExternMetricDefinitionImpl externMetricDefinition = new ExternMetricDefinitionImpl();
-    return modelSymbol;
+    return externMetricDefinition;
  }
  /**
@@ -275,10 +273,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public PartialitySymbol createPartialitySymbol()
+  public Expression createExpression()
  {
-    PartialitySymbolImpl partialitySymbol = new PartialitySymbolImpl();
+    ExpressionImpl expression = new ExpressionImpl();
-    return partialitySymbol;
+    return expression;
  }
  /**
@@ -287,10 +285,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public ExistSymbol createExistSymbol()
+  public IfElse createIfElse()
  {
-    ExistSymbolImpl existSymbol = new ExistSymbolImpl();
+    IfElseImpl ifElse = new IfElseImpl();
-    return existSymbol;
+    return ifElse;
  }
  /**
@@ -299,10 +297,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public EqualsSymbol createEqualsSymbol()
+  public Case createCase()
  {
-    EqualsSymbolImpl equalsSymbol = new EqualsSymbolImpl();
+    CaseImpl case_ = new CaseImpl();
-    return equalsSymbol;
+    return case_;
  }
  /**
@@ -311,10 +309,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public DataSymbol createDataSymbol()
+  public Count createCount()
  {
-    DataSymbolImpl dataSymbol = new DataSymbolImpl();
+    CountImpl count = new CountImpl();
-    return dataSymbol;
+    return count;
  }
  /**
@@ -323,10 +321,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public BooleanSymbol createBooleanSymbol()
+  public Aggregation createAggregation()
  {
-    BooleanSymbolImpl booleanSymbol = new BooleanSymbolImpl();
+    AggregationImpl aggregation = new AggregationImpl();
-    return booleanSymbol;
+    return aggregation;
  }
  /**
@@ -335,10 +333,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public IntegerSymbol createIntegerSymbol()
+  public Call createCall()
  {
-    IntegerSymbolImpl integerSymbol = new IntegerSymbolImpl();
+    CallImpl call = new CallImpl();
-    return integerSymbol;
+    return call;
  }
  /**
@@ -347,10 +345,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public RealSymbol createRealSymbol()
+  public ArgumentList createArgumentList()
  {
-    RealSymbolImpl realSymbol = new RealSymbolImpl();
+    ArgumentListImpl argumentList = new ArgumentListImpl();
-    return realSymbol;
+    return argumentList;
  }
  /**
@@ -359,10 +357,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public StringSymbol createStringSymbol()
+  public Argument createArgument()
  {
-    StringSymbolImpl stringSymbol = new StringSymbolImpl();
+    ArgumentImpl argument = new ArgumentImpl();
-    return stringSymbol;
+    return argument;
  }
  /**
@@ -371,10 +369,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public ComplexObject createComplexObject()
+  public ExpressionArgument createExpressionArgument()
  {
-    ComplexObjectImpl complexObject = new ComplexObjectImpl();
+    ExpressionArgumentImpl expressionArgument = new ExpressionArgumentImpl();
-    return complexObject;
+    return expressionArgument;
  }
  /**
@@ -383,10 +381,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public org.eclipse.viatra.solver.language.solverLanguage.Object createObject()
+  public StarArgument createStarArgument()
  {
-    ObjectImpl object = new ObjectImpl();
+    StarArgumentImpl starArgument = new StarArgumentImpl();
-    return object;
+    return starArgument;
  }
  /**
@@ -395,10 +393,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public NamedObject createNamedObject()
+  public TypedArgument createTypedArgument()
  {
-    NamedObjectImpl namedObject = new NamedObjectImpl();
+    TypedArgumentImpl typedArgument = new TypedArgumentImpl();
-    return namedObject;
+    return typedArgument;
  }
  /**
@@ -407,10 +405,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public UnnamedObject createUnnamedObject()
+  public TypedStarArgument createTypedStarArgument()
  {
-    UnnamedObjectImpl unnamedObject = new UnnamedObjectImpl();
+    TypedStarArgumentImpl typedStarArgument = new TypedStarArgumentImpl();
-    return unnamedObject;
+    return typedStarArgument;
  }
  /**
@@ -419,10 +417,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public DataObject createDataObject()
+  public Reference createReference()
  {
-    DataObjectImpl dataObject = new DataObjectImpl();
+    ReferenceImpl reference = new ReferenceImpl();
-    return dataObject;
+    return reference;
  }
  /**
@@ -431,10 +429,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public BooleanObject createBooleanObject()
+  public Interval createInterval()
  {
-    BooleanObjectImpl booleanObject = new BooleanObjectImpl();
+    IntervalImpl interval = new IntervalImpl();
-    return booleanObject;
+    return interval;
  }
  /**
@@ -443,10 +441,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public IntObject createIntObject()
+  public Literal createLiteral()
  {
-    IntObjectImpl intObject = new IntObjectImpl();
+    LiteralImpl literal = new LiteralImpl();
-    return intObject;
+    return literal;
  }
  /**
@@ -455,10 +453,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public RealObject createRealObject()
+  public LogicLiteral createLogicLiteral()
  {
-    RealObjectImpl realObject = new RealObjectImpl();
+    LogicLiteralImpl logicLiteral = new LogicLiteralImpl();
-    return realObject;
+    return logicLiteral;
  }
  /**
@@ -467,10 +465,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public StringObject createStringObject()
+  public NumericLiteral createNumericLiteral()
  {
-    StringObjectImpl stringObject = new StringObjectImpl();
+    NumericLiteralImpl numericLiteral = new NumericLiteralImpl();
-    return stringObject;
+    return numericLiteral;
  }
  /**
@@ -479,10 +477,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public Predicate createPredicate()
+  public InfinityLiteral createInfinityLiteral()
  {
-    PredicateImpl predicate = new PredicateImpl();
+    InfinityLiteralImpl infinityLiteral = new InfinityLiteralImpl();
-    return predicate;
+    return infinityLiteral;
  }
  /**
@@ -491,10 +489,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public Parameter createParameter()
+  public EmptyIntervalLiteral createEmptyIntervalLiteral()
  {
-    ParameterImpl parameter = new ParameterImpl();
+    EmptyIntervalLiteralImpl emptyIntervalLiteral = new EmptyIntervalLiteralImpl();
-    return parameter;
+    return emptyIntervalLiteral;
  }
  /**
@@ -503,10 +501,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public PatternBody createPatternBody()
+  public StringLiteral createStringLiteral()
  {
-    PatternBodyImpl patternBody = new PatternBodyImpl();
+    StringLiteralImpl stringLiteral = new StringLiteralImpl();
-    return patternBody;
+    return stringLiteral;
  }
  /**
@@ -515,10 +513,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public Polarity createPolarity()
+  public MemberDefinition createMemberDefinition()
  {
-    PolarityImpl polarity = new PolarityImpl();
+    MemberDefinitionImpl memberDefinition = new MemberDefinitionImpl();
-    return polarity;
+    return memberDefinition;
  }
  /**
@@ -527,10 +525,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public Constraint createConstraint()
+  public Multiplicity createMultiplicity()
  {
-    ConstraintImpl constraint = new ConstraintImpl();
+    MultiplicityImpl multiplicity = new MultiplicityImpl();
-    return constraint;
+    return multiplicity;
  }
  /**
@@ -539,10 +537,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public ClosureType createClosureType()
+  public ManyMultiplicity createManyMultiplicity()
  {
-    ClosureTypeImpl closureType = new ClosureTypeImpl();
+    ManyMultiplicityImpl manyMultiplicity = new ManyMultiplicityImpl();
-    return closureType;
+    return manyMultiplicity;
  }
  /**
@@ -551,10 +549,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public Literal createLiteral()
+  public ExactMultiplicity createExactMultiplicity()
  {
-    LiteralImpl literal = new LiteralImpl();
+    ExactMultiplicityImpl exactMultiplicity = new ExactMultiplicityImpl();
-    return literal;
+    return exactMultiplicity;
  }
  /**
@@ -563,10 +561,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public Variable createVariable()
+  public BoundedMultiplicity createBoundedMultiplicity()
  {
-    VariableImpl variable = new VariableImpl();
+    BoundedMultiplicityImpl boundedMultiplicity = new BoundedMultiplicityImpl();
-    return variable;
+    return boundedMultiplicity;
  }
  /**
@@ -575,10 +573,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public AllInstances createAllInstances()
+  public ScopeDefinition createScopeDefinition()
  {
-    AllInstancesImpl allInstances = new AllInstancesImpl();
+    ScopeDefinitionImpl scopeDefinition = new ScopeDefinitionImpl();
-    return allInstances;
+    return scopeDefinition;
  }
  /**
@@ -587,10 +585,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public AllObjects createAllObjects()
+  public ExactScopeDefinition createExactScopeDefinition()
  {
-    AllObjectsImpl allObjects = new AllObjectsImpl();
+    ExactScopeDefinitionImpl exactScopeDefinition = new ExactScopeDefinitionImpl();
-    return allObjects;
+    return exactScopeDefinition;
  }
  /**
@@ -599,10 +597,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public DefaultInterpretation createDefaultInterpretation()
+  public BoundedScopeDefinition createBoundedScopeDefinition()
  {
-    DefaultInterpretationImpl defaultInterpretation = new DefaultInterpretationImpl();
+    BoundedScopeDefinitionImpl boundedScopeDefinition = new BoundedScopeDefinitionImpl();
-    return defaultInterpretation;
+    return boundedScopeDefinition;
  }
  /**
@@ -611,10 +609,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public CDInterpretation createCDInterpretation()
+  public LowerBoundedScopeDefinition createLowerBoundedScopeDefinition()
  {
-    CDInterpretationImpl cdInterpretation = new CDInterpretationImpl();
+    LowerBoundedScopeDefinitionImpl lowerBoundedScopeDefinition = new LowerBoundedScopeDefinitionImpl();
-    return cdInterpretation;
+    return lowerBoundedScopeDefinition;
  }
  /**
@@ -623,10 +621,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public ClassInterpretation createClassInterpretation()
+  public ObjectiveDefinition createObjectiveDefinition()
  {
-    ClassInterpretationImpl classInterpretation = new ClassInterpretationImpl();
+    ObjectiveDefinitionImpl objectiveDefinition = new ObjectiveDefinitionImpl();
-    return classInterpretation;
+    return objectiveDefinition;
  }
  /**
@@ -635,10 +633,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public EnumInterpretation createEnumInterpretation()
+  public NamedElement createNamedElement()
  {
-    EnumInterpretationImpl enumInterpretation = new EnumInterpretationImpl();
+    NamedElementImpl namedElement = new NamedElementImpl();
-    return enumInterpretation;
+    return namedElement;
  }
  /**
@@ -647,10 +645,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public FieldRelationInterpretation createFieldRelationInterpretation()
+  public Assertion createAssertion()
  {
-    FieldRelationInterpretationImpl fieldRelationInterpretation = new FieldRelationInterpretationImpl();
+    AssertionImpl assertion = new AssertionImpl();
-    return fieldRelationInterpretation;
+    return assertion;
  }
  /**
@@ -659,10 +657,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public GlobalRelationInterpretation createGlobalRelationInterpretation()
+  public Disjunction createDisjunction()
  {
-    GlobalRelationInterpretationImpl globalRelationInterpretation = new GlobalRelationInterpretationImpl();
+    DisjunctionImpl disjunction = new DisjunctionImpl();
-    return globalRelationInterpretation;
+    return disjunction;
  }
  /**
@@ -671,10 +669,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public MultiplicityDefinition createMultiplicityDefinition()
+  public Switch createSwitch()
  {
-    MultiplicityDefinitionImpl multiplicityDefinition = new MultiplicityDefinitionImpl();
+    SwitchImpl switch_ = new SwitchImpl();
-    return multiplicityDefinition;
+    return switch_;
  }
  /**
@@ -683,10 +681,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public BooleanTrue createBooleanTrue()
+  public Conjunction createConjunction()
  {
-    BooleanTrueImpl booleanTrue = new BooleanTrueImpl();
+    ConjunctionImpl conjunction = new ConjunctionImpl();
-    return booleanTrue;
+    return conjunction;
  }
  /**
@@ -695,10 +693,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public BooleanFalse createBooleanFalse()
+  public Comparison createComparison()
  {
-    BooleanFalseImpl booleanFalse = new BooleanFalseImpl();
+    ComparisonImpl comparison = new ComparisonImpl();
-    return booleanFalse;
+    return comparison;
  }
  /**
@@ -707,10 +705,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public True createTrue()
+  public BinaryExpression createBinaryExpression()
  {
-    TrueImpl true_ = new TrueImpl();
+    BinaryExpressionImpl binaryExpression = new BinaryExpressionImpl();
-    return true_;
+    return binaryExpression;
  }
  /**
@@ -719,10 +717,10 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * @generated
   */
  @Override
-  public False createFalse()
+  public UnaryExpression createUnaryExpression()
  {
-    FalseImpl false_ = new FalseImpl();
+    UnaryExpressionImpl unaryExpression = new UnaryExpressionImpl();
-    return false_;
+    return unaryExpression;
  }
  /**
@@ -730,11 +728,11 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * <!-- end-user-doc -->
   * @generated
   */
-  @Override
+  public MetricType createMetricTypeFromString(EDataType eDataType, String initialValue)
-  public Unknown createUnknown()
  {
-    UnknownImpl unknown = new UnknownImpl();
+    MetricType result = MetricType.get(initialValue);
-    return unknown;
+    if (result == null) throw new IllegalArgumentException("The value '" + initialValue + "' is not a valid enumerator of '" + eDataType.getName() + "'");
+    return result;
  }
  /**
@@ -742,11 +740,9 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * <!-- end-user-doc -->
   * @generated
   */
-  @Override
+  public String convertMetricTypeToString(EDataType eDataType, Object instanceValue)
-  public org.eclipse.viatra.solver.language.solverLanguage.Error createError()
  {
-    ErrorImpl error = new ErrorImpl();
+    return instanceValue == null ? null : instanceValue.toString();
-    return error;
  }
  /**
@@ -754,11 +750,11 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * <!-- end-user-doc -->
   * @generated
   */
-  @Override
+  public BinaryOperator createBinaryOperatorFromString(EDataType eDataType, String initialValue)
-  public Positive createPositive()
  {
-    PositiveImpl positive = new PositiveImpl();
+    BinaryOperator result = BinaryOperator.get(initialValue);
-    return positive;
+    if (result == null) throw new IllegalArgumentException("The value '" + initialValue + "' is not a valid enumerator of '" + eDataType.getName() + "'");
+    return result;
  }
  /**
@@ -766,11 +762,9 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * <!-- end-user-doc -->
   * @generated
   */
-  @Override
+  public String convertBinaryOperatorToString(EDataType eDataType, Object instanceValue)
-  public Negative createNegative()
  {
-    NegativeImpl negative = new NegativeImpl();
+    return instanceValue == null ? null : instanceValue.toString();
-    return negative;
  }
  /**
@@ -778,11 +772,11 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * <!-- end-user-doc -->
   * @generated
   */
-  @Override
+  public UnaryOp createUnaryOpFromString(EDataType eDataType, String initialValue)
-  public ReflexiveClosure createReflexiveClosure()
  {
-    ReflexiveClosureImpl reflexiveClosure = new ReflexiveClosureImpl();
+    UnaryOp result = UnaryOp.get(initialValue);
-    return reflexiveClosure;
+    if (result == null) throw new IllegalArgumentException("The value '" + initialValue + "' is not a valid enumerator of '" + eDataType.getName() + "'");
+    return result;
  }
  /**
@@ -790,11 +784,75 @@ public class SolverLanguageFactoryImpl extends EFactoryImpl implements SolverLan
   * <!-- end-user-doc -->
   * @generated
   */
-  @Override
+  public String convertUnaryOpToString(EDataType eDataType, Object instanceValue)
-  public IrreflexiveClosure createIrreflexiveClosure()
+  {
+    return instanceValue == null ? null : instanceValue.toString();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public AggregationOp createAggregationOpFromString(EDataType eDataType, String initialValue)
+  {
+    AggregationOp result = AggregationOp.get(initialValue);
+    if (result == null) throw new IllegalArgumentException("The value '" + initialValue + "' is not a valid enumerator of '" + eDataType.getName() + "'");
+    return result;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public String convertAggregationOpToString(EDataType eDataType, Object instanceValue)
+  {
+    return instanceValue == null ? null : instanceValue.toString();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public LogicValue createLogicValueFromString(EDataType eDataType, String initialValue)
+  {
+    LogicValue result = LogicValue.get(initialValue);
+    if (result == null) throw new IllegalArgumentException("The value '" + initialValue + "' is not a valid enumerator of '" + eDataType.getName() + "'");
+    return result;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public String convertLogicValueToString(EDataType eDataType, Object instanceValue)
+  {
+    return instanceValue == null ? null : instanceValue.toString();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public ObjectiveKind createObjectiveKindFromString(EDataType eDataType, String initialValue)
+  {
+    ObjectiveKind result = ObjectiveKind.get(initialValue);
+    if (result == null) throw new IllegalArgumentException("The value '" + initialValue + "' is not a valid enumerator of '" + eDataType.getName() + "'");
+    return result;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public String convertObjectiveKindToString(EDataType eDataType, Object instanceValue)
  {
-    IrreflexiveClosureImpl irreflexiveClosure = new IrreflexiveClosureImpl();
+    return instanceValue == null ? null : instanceValue.toString();
-    return irreflexiveClosure;
  }
  /**
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SolverLanguagePackageImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SolverLanguagePackageImpl.java
index f617be3f..393a2545 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SolverLanguagePackageImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SolverLanguagePackageImpl.java
@@ -1,67 +1,70 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
 import org.eclipse.emf.ecore.EAttribute;
 import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.EEnum;
 import org.eclipse.emf.ecore.EPackage;
 import org.eclipse.emf.ecore.EReference;
 import org.eclipse.emf.ecore.impl.EPackageImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.AllInstances;
+import org.eclipse.viatra.solver.language.solverLanguage.Aggregation;
-import org.eclipse.viatra.solver.language.solverLanguage.AllObjects;
+import org.eclipse.viatra.solver.language.solverLanguage.AggregationOp;
-import org.eclipse.viatra.solver.language.solverLanguage.BasicInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.Argument;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanFalse;
+import org.eclipse.viatra.solver.language.solverLanguage.ArgumentList;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanObject;
+import org.eclipse.viatra.solver.language.solverLanguage.Assertion;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.BinaryExpression;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanTrue;
+import org.eclipse.viatra.solver.language.solverLanguage.BinaryOperator;
-import org.eclipse.viatra.solver.language.solverLanguage.BooleanValue;
+import org.eclipse.viatra.solver.language.solverLanguage.BoundedMultiplicity;
-import org.eclipse.viatra.solver.language.solverLanguage.CDInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.BoundedScopeDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.ClassInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.Call;
-import org.eclipse.viatra.solver.language.solverLanguage.ClosureType;
+import org.eclipse.viatra.solver.language.solverLanguage.Case;
-import org.eclipse.viatra.solver.language.solverLanguage.ComplexObject;
+import org.eclipse.viatra.solver.language.solverLanguage.Comparison;
-import org.eclipse.viatra.solver.language.solverLanguage.Constraint;
+import org.eclipse.viatra.solver.language.solverLanguage.Conjunction;
-import org.eclipse.viatra.solver.language.solverLanguage.DataObject;
+import org.eclipse.viatra.solver.language.solverLanguage.Count;
-import org.eclipse.viatra.solver.language.solverLanguage.DataSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.DefaultDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.DefaultInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.Disjunction;
-import org.eclipse.viatra.solver.language.solverLanguage.EnumInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.EmptyIntervalLiteral;
-import org.eclipse.viatra.solver.language.solverLanguage.EqualsSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.ExactMultiplicity;
-import org.eclipse.viatra.solver.language.solverLanguage.ExistSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.ExactScopeDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.False;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
-import org.eclipse.viatra.solver.language.solverLanguage.FieldRelationInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.ExpressionArgument;
-import org.eclipse.viatra.solver.language.solverLanguage.GlobalRelationInterpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.ExternMetricDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.IntObject;
+import org.eclipse.viatra.solver.language.solverLanguage.ExternPredicateDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.IntegerSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.IfElse;
-import org.eclipse.viatra.solver.language.solverLanguage.Interpretation;
+import org.eclipse.viatra.solver.language.solverLanguage.InfinityLiteral;
-import org.eclipse.viatra.solver.language.solverLanguage.IrreflexiveClosure;
+import org.eclipse.viatra.solver.language.solverLanguage.Interval;
 import org.eclipse.viatra.solver.language.solverLanguage.Literal;
-import org.eclipse.viatra.solver.language.solverLanguage.ModelSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.LogicLiteral;
-import org.eclipse.viatra.solver.language.solverLanguage.MultiplicityDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.LogicValue;
-import org.eclipse.viatra.solver.language.solverLanguage.NamedObject;
+import org.eclipse.viatra.solver.language.solverLanguage.LowerBoundedScopeDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.Negative;
+import org.eclipse.viatra.solver.language.solverLanguage.ManyMultiplicity;
-import org.eclipse.viatra.solver.language.solverLanguage.Parameter;
+import org.eclipse.viatra.solver.language.solverLanguage.MemberDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.PartialitySymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.MetricDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.PatternBody;
+import org.eclipse.viatra.solver.language.solverLanguage.MetricType;
-import org.eclipse.viatra.solver.language.solverLanguage.Polarity;
+import org.eclipse.viatra.solver.language.solverLanguage.Multiplicity;
-import org.eclipse.viatra.solver.language.solverLanguage.Positive;
+import org.eclipse.viatra.solver.language.solverLanguage.NamedElement;
-import org.eclipse.viatra.solver.language.solverLanguage.Predicate;
+import org.eclipse.viatra.solver.language.solverLanguage.NumericLiteral;
+import org.eclipse.viatra.solver.language.solverLanguage.ObjectiveDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.ObjectiveKind;
+import org.eclipse.viatra.solver.language.solverLanguage.PredicateDefinition;
 import org.eclipse.viatra.solver.language.solverLanguage.Problem;
-import org.eclipse.viatra.solver.language.solverLanguage.RealObject;
+import org.eclipse.viatra.solver.language.solverLanguage.Reference;
-import org.eclipse.viatra.solver.language.solverLanguage.RealSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.ScopeDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.ReflexiveClosure;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguageFactory;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+import org.eclipse.viatra.solver.language.solverLanguage.StarArgument;
 import org.eclipse.viatra.solver.language.solverLanguage.Statement;
-import org.eclipse.viatra.solver.language.solverLanguage.StringObject;
+import org.eclipse.viatra.solver.language.solverLanguage.StringLiteral;
-import org.eclipse.viatra.solver.language.solverLanguage.StringSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.Switch;
-import org.eclipse.viatra.solver.language.solverLanguage.Symbol;
+import org.eclipse.viatra.solver.language.solverLanguage.TypedArgument;
-import org.eclipse.viatra.solver.language.solverLanguage.True;
+import org.eclipse.viatra.solver.language.solverLanguage.TypedStarArgument;
-import org.eclipse.viatra.solver.language.solverLanguage.TruthValue;
+import org.eclipse.viatra.solver.language.solverLanguage.UnaryExpression;
-import org.eclipse.viatra.solver.language.solverLanguage.Unknown;
+import org.eclipse.viatra.solver.language.solverLanguage.UnaryOp;
-import org.eclipse.viatra.solver.language.solverLanguage.UnnamedObject;
+import org.eclipse.viatra.solver.language.solverLanguage.UnnamedErrorPrediateDefinition;
-import org.eclipse.viatra.solver.language.solverLanguage.Variable;
 /**
 * <!-- begin-user-doc -->
@@ -90,350 +93,350 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass booleanValueEClass = null;
+  private EClass predicateDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass truthValueEClass = null;
+  private EClass unnamedErrorPrediateDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass interpretationEClass = null;
+  private EClass defaultDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass basicInterpretationEClass = null;
+  private EClass externPredicateDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass symbolEClass = null;
+  private EClass metricDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass modelSymbolEClass = null;
+  private EClass externMetricDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass partialitySymbolEClass = null;
+  private EClass expressionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass existSymbolEClass = null;
+  private EClass ifElseEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass equalsSymbolEClass = null;
+  private EClass caseEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass dataSymbolEClass = null;
+  private EClass countEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass booleanSymbolEClass = null;
+  private EClass aggregationEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass integerSymbolEClass = null;
+  private EClass callEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass realSymbolEClass = null;
+  private EClass argumentListEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass stringSymbolEClass = null;
+  private EClass argumentEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass complexObjectEClass = null;
+  private EClass expressionArgumentEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass objectEClass = null;
+  private EClass starArgumentEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass namedObjectEClass = null;
+  private EClass typedArgumentEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass unnamedObjectEClass = null;
+  private EClass typedStarArgumentEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass dataObjectEClass = null;
+  private EClass referenceEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass booleanObjectEClass = null;
+  private EClass intervalEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass intObjectEClass = null;
+  private EClass literalEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass realObjectEClass = null;
+  private EClass logicLiteralEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass stringObjectEClass = null;
+  private EClass numericLiteralEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass predicateEClass = null;
+  private EClass infinityLiteralEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass parameterEClass = null;
+  private EClass emptyIntervalLiteralEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass patternBodyEClass = null;
+  private EClass stringLiteralEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass polarityEClass = null;
+  private EClass memberDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass constraintEClass = null;
+  private EClass multiplicityEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass closureTypeEClass = null;
+  private EClass manyMultiplicityEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass literalEClass = null;
+  private EClass exactMultiplicityEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass variableEClass = null;
+  private EClass boundedMultiplicityEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass allInstancesEClass = null;
+  private EClass scopeDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass allObjectsEClass = null;
+  private EClass exactScopeDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass defaultInterpretationEClass = null;
+  private EClass boundedScopeDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass cdInterpretationEClass = null;
+  private EClass lowerBoundedScopeDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass classInterpretationEClass = null;
+  private EClass objectiveDefinitionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass enumInterpretationEClass = null;
+  private EClass namedElementEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass fieldRelationInterpretationEClass = null;
+  private EClass assertionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass globalRelationInterpretationEClass = null;
+  private EClass disjunctionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass multiplicityDefinitionEClass = null;
+  private EClass switchEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass booleanTrueEClass = null;
+  private EClass conjunctionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass booleanFalseEClass = null;
+  private EClass comparisonEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass trueEClass = null;
+  private EClass binaryExpressionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass falseEClass = null;
+  private EClass unaryExpressionEClass = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass unknownEClass = null;
+  private EEnum metricTypeEEnum = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass errorEClass = null;
+  private EEnum binaryOperatorEEnum = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass positiveEClass = null;
+  private EEnum unaryOpEEnum = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass negativeEClass = null;
+  private EEnum aggregationOpEEnum = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass reflexiveClosureEClass = null;
+  private EEnum logicValueEEnum = null;
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  private EClass irreflexiveClosureEClass = null;
+  private EEnum objectiveKindEEnum = null;
  /**
   * Creates an instance of the model <b>Package</b>, registered with
@@ -537,9 +540,108 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getBooleanValue()
+  public EAttribute getStatement_Abstract()
+  {
+    return (EAttribute)statementEClass.getEStructuralFeatures().get(0);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getStatement_Name()
+  {
+    return (EAttribute)statementEClass.getEStructuralFeatures().get(1);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EReference getStatement_Superclasses()
+  {
+    return (EReference)statementEClass.getEStructuralFeatures().get(2);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EReference getStatement_Members()
+  {
+    return (EReference)statementEClass.getEStructuralFeatures().get(3);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getPredicateDefinition()
+  {
+    return predicateDefinitionEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EReference getPredicateDefinition_Head()
+  {
+    return (EReference)predicateDefinitionEClass.getEStructuralFeatures().get(0);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EReference getPredicateDefinition_Body()
+  {
+    return (EReference)predicateDefinitionEClass.getEStructuralFeatures().get(1);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getPredicateDefinition_Functional()
+  {
+    return (EAttribute)predicateDefinitionEClass.getEStructuralFeatures().get(2);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getPredicateDefinition_Error()
+  {
+    return (EAttribute)predicateDefinitionEClass.getEStructuralFeatures().get(3);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getUnnamedErrorPrediateDefinition()
  {
-    return booleanValueEClass;
+    return unnamedErrorPrediateDefinitionEClass;
  }
  /**
@@ -548,9 +650,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getTruthValue()
+  public EReference getUnnamedErrorPrediateDefinition_ArgumentList()
  {
-    return truthValueEClass;
+    return (EReference)unnamedErrorPrediateDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -559,9 +661,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getInterpretation()
+  public EReference getUnnamedErrorPrediateDefinition_Body()
  {
-    return interpretationEClass;
+    return (EReference)unnamedErrorPrediateDefinitionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -570,9 +672,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getBasicInterpretation()
+  public EClass getDefaultDefinition()
  {
-    return basicInterpretationEClass;
+    return defaultDefinitionEClass;
  }
  /**
@@ -581,9 +683,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getBasicInterpretation_Symbol()
+  public EReference getDefaultDefinition_Head()
  {
-    return (EReference)basicInterpretationEClass.getEStructuralFeatures().get(0);
+    return (EReference)defaultDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -592,9 +694,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getBasicInterpretation_Objects()
+  public EReference getDefaultDefinition_Range()
  {
-    return (EReference)basicInterpretationEClass.getEStructuralFeatures().get(1);
+    return (EReference)defaultDefinitionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -603,9 +705,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getBasicInterpretation_Value()
+  public EClass getExternPredicateDefinition()
  {
-    return (EReference)basicInterpretationEClass.getEStructuralFeatures().get(2);
+    return externPredicateDefinitionEClass;
  }
  /**
@@ -614,9 +716,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getSymbol()
+  public EReference getExternPredicateDefinition_Head()
  {
-    return symbolEClass;
+    return (EReference)externPredicateDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -625,9 +727,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getModelSymbol()
+  public EClass getMetricDefinition()
  {
-    return modelSymbolEClass;
+    return metricDefinitionEClass;
  }
  /**
@@ -636,9 +738,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getModelSymbol_Name()
+  public EReference getMetricDefinition_Head()
  {
-    return (EAttribute)modelSymbolEClass.getEStructuralFeatures().get(0);
+    return (EReference)metricDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -647,9 +749,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getPartialitySymbol()
+  public EReference getMetricDefinition_Body()
  {
-    return partialitySymbolEClass;
+    return (EReference)metricDefinitionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -658,9 +760,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getExistSymbol()
+  public EAttribute getMetricDefinition_Type()
  {
-    return existSymbolEClass;
+    return (EAttribute)metricDefinitionEClass.getEStructuralFeatures().get(2);
  }
  /**
@@ -669,9 +771,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getEqualsSymbol()
+  public EClass getExternMetricDefinition()
  {
-    return equalsSymbolEClass;
+    return externMetricDefinitionEClass;
  }
  /**
@@ -680,9 +782,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getDataSymbol()
+  public EAttribute getExternMetricDefinition_Type()
  {
-    return dataSymbolEClass;
+    return (EAttribute)externMetricDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -691,9 +793,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getBooleanSymbol()
+  public EReference getExternMetricDefinition_Head()
  {
-    return booleanSymbolEClass;
+    return (EReference)externMetricDefinitionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -702,9 +804,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getIntegerSymbol()
+  public EClass getExpression()
  {
-    return integerSymbolEClass;
+    return expressionEClass;
  }
  /**
@@ -713,9 +815,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getRealSymbol()
+  public EClass getIfElse()
  {
-    return realSymbolEClass;
+    return ifElseEClass;
  }
  /**
@@ -724,9 +826,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getStringSymbol()
+  public EReference getIfElse_Condition()
  {
-    return stringSymbolEClass;
+    return (EReference)ifElseEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -735,9 +837,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getComplexObject()
+  public EReference getIfElse_Then()
  {
-    return complexObjectEClass;
+    return (EReference)ifElseEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -746,9 +848,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getObject()
+  public EReference getIfElse_Else()
  {
-    return objectEClass;
+    return (EReference)ifElseEClass.getEStructuralFeatures().get(2);
  }
  /**
@@ -757,9 +859,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getNamedObject()
+  public EClass getCase()
  {
-    return namedObjectEClass;
+    return caseEClass;
  }
  /**
@@ -768,9 +870,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getNamedObject_Name()
+  public EReference getCase_Condition()
  {
-    return (EAttribute)namedObjectEClass.getEStructuralFeatures().get(0);
+    return (EReference)caseEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -779,9 +881,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getUnnamedObject()
+  public EReference getCase_Body()
  {
-    return unnamedObjectEClass;
+    return (EReference)caseEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -790,9 +892,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getUnnamedObject_Name()
+  public EClass getCount()
  {
-    return (EAttribute)unnamedObjectEClass.getEStructuralFeatures().get(0);
+    return countEClass;
  }
  /**
@@ -801,9 +903,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getDataObject()
+  public EReference getCount_Body()
  {
-    return dataObjectEClass;
+    return (EReference)countEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -812,9 +914,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getBooleanObject()
+  public EClass getAggregation()
  {
-    return booleanObjectEClass;
+    return aggregationEClass;
  }
  /**
@@ -823,9 +925,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getBooleanObject_Value()
+  public EAttribute getAggregation_Op()
  {
-    return (EReference)booleanObjectEClass.getEStructuralFeatures().get(0);
+    return (EAttribute)aggregationEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -834,9 +936,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getIntObject()
+  public EReference getAggregation_Body()
  {
-    return intObjectEClass;
+    return (EReference)aggregationEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -845,9 +947,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getIntObject_Value()
+  public EReference getAggregation_Condition()
  {
-    return (EAttribute)intObjectEClass.getEStructuralFeatures().get(0);
+    return (EReference)aggregationEClass.getEStructuralFeatures().get(2);
  }
  /**
@@ -856,9 +958,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getRealObject()
+  public EClass getCall()
  {
-    return realObjectEClass;
+    return callEClass;
  }
  /**
@@ -867,9 +969,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getRealObject_Value()
+  public EReference getCall_Functor()
  {
-    return (EAttribute)realObjectEClass.getEStructuralFeatures().get(0);
+    return (EReference)callEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -878,9 +980,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getStringObject()
+  public EReference getCall_ArgumentList()
  {
-    return stringObjectEClass;
+    return (EReference)callEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -889,9 +991,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getStringObject_Value()
+  public EAttribute getCall_TransitiveClosure()
  {
-    return (EAttribute)stringObjectEClass.getEStructuralFeatures().get(0);
+    return (EAttribute)callEClass.getEStructuralFeatures().get(2);
  }
  /**
@@ -900,9 +1002,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getPredicate()
+  public EAttribute getCall_ReflexiveTransitiveClosure()
  {
-    return predicateEClass;
+    return (EAttribute)callEClass.getEStructuralFeatures().get(3);
  }
  /**
@@ -911,9 +1013,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getPredicate_IsError()
+  public EClass getArgumentList()
  {
-    return (EAttribute)predicateEClass.getEStructuralFeatures().get(0);
+    return argumentListEClass;
  }
  /**
@@ -922,9 +1024,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getPredicate_Symbol()
+  public EReference getArgumentList_Arguments()
  {
-    return (EReference)predicateEClass.getEStructuralFeatures().get(1);
+    return (EReference)argumentListEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -933,9 +1035,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getPredicate_Parameters()
+  public EClass getArgument()
  {
-    return (EReference)predicateEClass.getEStructuralFeatures().get(2);
+    return argumentEClass;
  }
  /**
@@ -944,9 +1046,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getPredicate_Bodies()
+  public EClass getExpressionArgument()
  {
-    return (EReference)predicateEClass.getEStructuralFeatures().get(3);
+    return expressionArgumentEClass;
  }
  /**
@@ -955,9 +1057,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getParameter()
+  public EReference getExpressionArgument_Body()
  {
-    return parameterEClass;
+    return (EReference)expressionArgumentEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -966,9 +1068,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getParameter_Variable()
+  public EClass getStarArgument()
  {
-    return (EReference)parameterEClass.getEStructuralFeatures().get(0);
+    return starArgumentEClass;
  }
  /**
@@ -977,9 +1079,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getParameter_Type()
+  public EClass getTypedArgument()
  {
-    return (EReference)parameterEClass.getEStructuralFeatures().get(1);
+    return typedArgumentEClass;
  }
  /**
@@ -988,9 +1090,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getPatternBody()
+  public EReference getTypedArgument_Type()
  {
-    return patternBodyEClass;
+    return (EReference)typedArgumentEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -999,9 +1101,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getPatternBody_Constraints()
+  public EReference getTypedArgument_Variable()
  {
-    return (EReference)patternBodyEClass.getEStructuralFeatures().get(0);
+    return (EReference)typedArgumentEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1010,9 +1112,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getPolarity()
+  public EClass getTypedStarArgument()
  {
-    return polarityEClass;
+    return typedStarArgumentEClass;
  }
  /**
@@ -1021,9 +1123,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getConstraint()
+  public EReference getTypedStarArgument_Type()
  {
-    return constraintEClass;
+    return (EReference)typedStarArgumentEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1032,9 +1134,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getConstraint_Polarity()
+  public EClass getReference()
  {
-    return (EReference)constraintEClass.getEStructuralFeatures().get(0);
+    return referenceEClass;
  }
  /**
@@ -1043,9 +1145,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getConstraint_Symbol()
+  public EReference getReference_Referred()
  {
-    return (EReference)constraintEClass.getEStructuralFeatures().get(1);
+    return (EReference)referenceEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1054,9 +1156,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getConstraint_Params()
+  public EClass getInterval()
  {
-    return (EReference)constraintEClass.getEStructuralFeatures().get(2);
+    return intervalEClass;
  }
  /**
@@ -1065,9 +1167,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getConstraint_ClosureType()
+  public EReference getInterval_LowerBound()
  {
-    return (EReference)constraintEClass.getEStructuralFeatures().get(3);
+    return (EReference)intervalEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1076,9 +1178,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getClosureType()
+  public EReference getInterval_UpperBound()
  {
-    return closureTypeEClass;
+    return (EReference)intervalEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1098,9 +1200,207 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getVariable()
+  public EClass getLogicLiteral()
+  {
+    return logicLiteralEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getLogicLiteral_Value()
+  {
+    return (EAttribute)logicLiteralEClass.getEStructuralFeatures().get(0);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getNumericLiteral()
+  {
+    return numericLiteralEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getNumericLiteral_Value()
+  {
+    return (EAttribute)numericLiteralEClass.getEStructuralFeatures().get(0);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getInfinityLiteral()
+  {
+    return infinityLiteralEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getEmptyIntervalLiteral()
+  {
+    return emptyIntervalLiteralEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getStringLiteral()
+  {
+    return stringLiteralEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getStringLiteral_Value()
+  {
+    return (EAttribute)stringLiteralEClass.getEStructuralFeatures().get(0);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getMemberDefinition()
+  {
+    return memberDefinitionEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getMemberDefinition_Containment()
+  {
+    return (EAttribute)memberDefinitionEClass.getEStructuralFeatures().get(0);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EReference getMemberDefinition_Type()
+  {
+    return (EReference)memberDefinitionEClass.getEStructuralFeatures().get(1);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EReference getMemberDefinition_Multiplicity()
+  {
+    return (EReference)memberDefinitionEClass.getEStructuralFeatures().get(2);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getMemberDefinition_Name()
+  {
+    return (EAttribute)memberDefinitionEClass.getEStructuralFeatures().get(3);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EReference getMemberDefinition_Opposite()
+  {
+    return (EReference)memberDefinitionEClass.getEStructuralFeatures().get(4);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getMultiplicity()
+  {
+    return multiplicityEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getManyMultiplicity()
+  {
+    return manyMultiplicityEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getExactMultiplicity()
+  {
+    return exactMultiplicityEClass;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EAttribute getExactMultiplicity_Multiplicity()
+  {
+    return (EAttribute)exactMultiplicityEClass.getEStructuralFeatures().get(0);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EClass getBoundedMultiplicity()
  {
-    return variableEClass;
+    return boundedMultiplicityEClass;
  }
  /**
@@ -1109,9 +1409,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getVariable_Name()
+  public EAttribute getBoundedMultiplicity_LowerBound()
  {
-    return (EAttribute)variableEClass.getEStructuralFeatures().get(0);
+    return (EAttribute)boundedMultiplicityEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1120,9 +1420,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getAllInstances()
+  public EAttribute getBoundedMultiplicity_UpperBound()
  {
-    return allInstancesEClass;
+    return (EAttribute)boundedMultiplicityEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1131,9 +1431,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getAllInstances_Symbol()
+  public EClass getScopeDefinition()
  {
-    return (EReference)allInstancesEClass.getEStructuralFeatures().get(0);
+    return scopeDefinitionEClass;
  }
  /**
@@ -1142,9 +1442,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getAllObjects()
+  public EReference getScopeDefinition_Type()
  {
-    return allObjectsEClass;
+    return (EReference)scopeDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1153,9 +1453,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getDefaultInterpretation()
+  public EClass getExactScopeDefinition()
  {
-    return defaultInterpretationEClass;
+    return exactScopeDefinitionEClass;
  }
  /**
@@ -1164,9 +1464,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getDefaultInterpretation_Interpretation()
+  public EAttribute getExactScopeDefinition_ExactScope()
  {
-    return (EReference)defaultInterpretationEClass.getEStructuralFeatures().get(0);
+    return (EAttribute)exactScopeDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1175,9 +1475,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getCDInterpretation()
+  public EClass getBoundedScopeDefinition()
  {
-    return cdInterpretationEClass;
+    return boundedScopeDefinitionEClass;
  }
  /**
@@ -1186,9 +1486,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getClassInterpretation()
+  public EAttribute getBoundedScopeDefinition_LowerBound()
  {
-    return classInterpretationEClass;
+    return (EAttribute)boundedScopeDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1197,9 +1497,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getClassInterpretation_Abstract()
+  public EAttribute getBoundedScopeDefinition_UpperBound()
  {
-    return (EAttribute)classInterpretationEClass.getEStructuralFeatures().get(0);
+    return (EAttribute)boundedScopeDefinitionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1208,9 +1508,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getClassInterpretation_Symbol()
+  public EClass getLowerBoundedScopeDefinition()
  {
-    return (EReference)classInterpretationEClass.getEStructuralFeatures().get(1);
+    return lowerBoundedScopeDefinitionEClass;
  }
  /**
@@ -1219,9 +1519,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getClassInterpretation_Supertypes()
+  public EAttribute getLowerBoundedScopeDefinition_LowerBound()
  {
-    return (EReference)classInterpretationEClass.getEStructuralFeatures().get(2);
+    return (EAttribute)lowerBoundedScopeDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1230,9 +1530,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getClassInterpretation_Fielt()
+  public EClass getObjectiveDefinition()
  {
-    return (EReference)classInterpretationEClass.getEStructuralFeatures().get(3);
+    return objectiveDefinitionEClass;
  }
  /**
@@ -1241,9 +1541,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getEnumInterpretation()
+  public EAttribute getObjectiveDefinition_Kind()
  {
-    return enumInterpretationEClass;
+    return (EAttribute)objectiveDefinitionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1252,9 +1552,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getEnumInterpretation_Symbol()
+  public EReference getObjectiveDefinition_Objective()
  {
-    return (EReference)enumInterpretationEClass.getEStructuralFeatures().get(0);
+    return (EReference)objectiveDefinitionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1263,9 +1563,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getEnumInterpretation_Objects()
+  public EClass getNamedElement()
  {
-    return (EReference)enumInterpretationEClass.getEStructuralFeatures().get(1);
+    return namedElementEClass;
  }
  /**
@@ -1274,9 +1574,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getFieldRelationInterpretation()
+  public EAttribute getNamedElement_Name()
  {
-    return fieldRelationInterpretationEClass;
+    return (EAttribute)namedElementEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1285,9 +1585,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getFieldRelationInterpretation_Containment()
+  public EClass getAssertion()
  {
-    return (EAttribute)fieldRelationInterpretationEClass.getEStructuralFeatures().get(0);
+    return assertionEClass;
  }
  /**
@@ -1296,9 +1596,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getFieldRelationInterpretation_Symbol()
+  public EReference getAssertion_Body()
  {
-    return (EReference)fieldRelationInterpretationEClass.getEStructuralFeatures().get(1);
+    return (EReference)assertionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1307,9 +1607,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getFieldRelationInterpretation_Multiplicity()
+  public EReference getAssertion_Range()
  {
-    return (EReference)fieldRelationInterpretationEClass.getEStructuralFeatures().get(2);
+    return (EReference)assertionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1318,9 +1618,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getFieldRelationInterpretation_Target()
+  public EClass getDisjunction()
  {
-    return (EReference)fieldRelationInterpretationEClass.getEStructuralFeatures().get(3);
+    return disjunctionEClass;
  }
  /**
@@ -1329,9 +1629,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getGlobalRelationInterpretation()
+  public EReference getDisjunction_Children()
  {
-    return globalRelationInterpretationEClass;
+    return (EReference)disjunctionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1340,9 +1640,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getGlobalRelationInterpretation_Containment()
+  public EClass getSwitch()
  {
-    return (EAttribute)globalRelationInterpretationEClass.getEStructuralFeatures().get(0);
+    return switchEClass;
  }
  /**
@@ -1351,9 +1651,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getGlobalRelationInterpretation_Symbol()
+  public EReference getSwitch_Cases()
  {
-    return (EReference)globalRelationInterpretationEClass.getEStructuralFeatures().get(1);
+    return (EReference)switchEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1362,9 +1662,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getGlobalRelationInterpretation_SourceMultiplicity()
+  public EClass getConjunction()
  {
-    return (EReference)globalRelationInterpretationEClass.getEStructuralFeatures().get(2);
+    return conjunctionEClass;
  }
  /**
@@ -1373,9 +1673,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getGlobalRelationInterpretation_Source()
+  public EReference getConjunction_Children()
  {
-    return (EReference)globalRelationInterpretationEClass.getEStructuralFeatures().get(3);
+    return (EReference)conjunctionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1384,9 +1684,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getGlobalRelationInterpretation_TargetMultiplicity()
+  public EClass getComparison()
  {
-    return (EReference)globalRelationInterpretationEClass.getEStructuralFeatures().get(4);
+    return comparisonEClass;
  }
  /**
@@ -1395,9 +1695,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EReference getGlobalRelationInterpretation_Target()
+  public EReference getComparison_Left()
  {
-    return (EReference)globalRelationInterpretationEClass.getEStructuralFeatures().get(5);
+    return (EReference)comparisonEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1406,9 +1706,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getMultiplicityDefinition()
+  public EAttribute getComparison_Op()
  {
-    return multiplicityDefinitionEClass;
+    return (EAttribute)comparisonEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1417,9 +1717,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getMultiplicityDefinition_Lower()
+  public EReference getComparison_Right()
  {
-    return (EAttribute)multiplicityDefinitionEClass.getEStructuralFeatures().get(0);
+    return (EReference)comparisonEClass.getEStructuralFeatures().get(2);
  }
  /**
@@ -1428,9 +1728,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getMultiplicityDefinition_Upper()
+  public EClass getBinaryExpression()
  {
-    return (EAttribute)multiplicityDefinitionEClass.getEStructuralFeatures().get(1);
+    return binaryExpressionEClass;
  }
  /**
@@ -1439,9 +1739,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EAttribute getMultiplicityDefinition_UnlimitedUpper()
+  public EReference getBinaryExpression_Left()
  {
-    return (EAttribute)multiplicityDefinitionEClass.getEStructuralFeatures().get(2);
+    return (EReference)binaryExpressionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1450,9 +1750,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getBooleanTrue()
+  public EAttribute getBinaryExpression_Op()
  {
-    return booleanTrueEClass;
+    return (EAttribute)binaryExpressionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1461,9 +1761,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getBooleanFalse()
+  public EReference getBinaryExpression_Right()
  {
-    return booleanFalseEClass;
+    return (EReference)binaryExpressionEClass.getEStructuralFeatures().get(2);
  }
  /**
@@ -1472,9 +1772,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getTrue()
+  public EClass getUnaryExpression()
  {
-    return trueEClass;
+    return unaryExpressionEClass;
  }
  /**
@@ -1483,9 +1783,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getFalse()
+  public EAttribute getUnaryExpression_Op()
  {
-    return falseEClass;
+    return (EAttribute)unaryExpressionEClass.getEStructuralFeatures().get(0);
  }
  /**
@@ -1494,9 +1794,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getUnknown()
+  public EReference getUnaryExpression_Body()
  {
-    return unknownEClass;
+    return (EReference)unaryExpressionEClass.getEStructuralFeatures().get(1);
  }
  /**
@@ -1505,9 +1805,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getError()
+  public EEnum getMetricType()
  {
-    return errorEClass;
+    return metricTypeEEnum;
  }
  /**
@@ -1516,9 +1816,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getPositive()
+  public EEnum getBinaryOperator()
  {
-    return positiveEClass;
+    return binaryOperatorEEnum;
  }
  /**
@@ -1527,9 +1827,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getNegative()
+  public EEnum getUnaryOp()
  {
-    return negativeEClass;
+    return unaryOpEEnum;
  }
  /**
@@ -1538,9 +1838,9 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getReflexiveClosure()
+  public EEnum getAggregationOp()
  {
-    return reflexiveClosureEClass;
+    return aggregationOpEEnum;
  }
  /**
@@ -1549,9 +1849,20 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
   * @generated
   */
  @Override
-  public EClass getIrreflexiveClosure()
+  public EEnum getLogicValue()
  {
-    return irreflexiveClosureEClass;
+    return logicValueEEnum;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EEnum getObjectiveKind()
+  {
+    return objectiveKindEEnum;
  }
  /**
@@ -1589,149 +1900,173 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
    createEReference(problemEClass, PROBLEM__STATEMENTS);
    statementEClass = createEClass(STATEMENT);
+    createEAttribute(statementEClass, STATEMENT__ABSTRACT);
+    createEAttribute(statementEClass, STATEMENT__NAME);
+    createEReference(statementEClass, STATEMENT__SUPERCLASSES);
+    createEReference(statementEClass, STATEMENT__MEMBERS);
-    booleanValueEClass = createEClass(BOOLEAN_VALUE);
+    predicateDefinitionEClass = createEClass(PREDICATE_DEFINITION);
+    createEReference(predicateDefinitionEClass, PREDICATE_DEFINITION__HEAD);
-    truthValueEClass = createEClass(TRUTH_VALUE);
+    createEReference(predicateDefinitionEClass, PREDICATE_DEFINITION__BODY);
+    createEAttribute(predicateDefinitionEClass, PREDICATE_DEFINITION__FUNCTIONAL);
-    interpretationEClass = createEClass(INTERPRETATION);
+    createEAttribute(predicateDefinitionEClass, PREDICATE_DEFINITION__ERROR);
-    basicInterpretationEClass = createEClass(BASIC_INTERPRETATION);
-    createEReference(basicInterpretationEClass, BASIC_INTERPRETATION__SYMBOL);
-    createEReference(basicInterpretationEClass, BASIC_INTERPRETATION__OBJECTS);
-    createEReference(basicInterpretationEClass, BASIC_INTERPRETATION__VALUE);
-    symbolEClass = createEClass(SYMBOL);
-    modelSymbolEClass = createEClass(MODEL_SYMBOL);
+    unnamedErrorPrediateDefinitionEClass = createEClass(UNNAMED_ERROR_PREDIATE_DEFINITION);
-    createEAttribute(modelSymbolEClass, MODEL_SYMBOL__NAME);
+    createEReference(unnamedErrorPrediateDefinitionEClass, UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST);
+    createEReference(unnamedErrorPrediateDefinitionEClass, UNNAMED_ERROR_PREDIATE_DEFINITION__BODY);
-    partialitySymbolEClass = createEClass(PARTIALITY_SYMBOL);
+    defaultDefinitionEClass = createEClass(DEFAULT_DEFINITION);
+    createEReference(defaultDefinitionEClass, DEFAULT_DEFINITION__HEAD);
+    createEReference(defaultDefinitionEClass, DEFAULT_DEFINITION__RANGE);
-    existSymbolEClass = createEClass(EXIST_SYMBOL);
+    externPredicateDefinitionEClass = createEClass(EXTERN_PREDICATE_DEFINITION);
+    createEReference(externPredicateDefinitionEClass, EXTERN_PREDICATE_DEFINITION__HEAD);
-    equalsSymbolEClass = createEClass(EQUALS_SYMBOL);
+    metricDefinitionEClass = createEClass(METRIC_DEFINITION);
+    createEReference(metricDefinitionEClass, METRIC_DEFINITION__HEAD);
+    createEReference(metricDefinitionEClass, METRIC_DEFINITION__BODY);
+    createEAttribute(metricDefinitionEClass, METRIC_DEFINITION__TYPE);
-    dataSymbolEClass = createEClass(DATA_SYMBOL);
+    externMetricDefinitionEClass = createEClass(EXTERN_METRIC_DEFINITION);
+    createEAttribute(externMetricDefinitionEClass, EXTERN_METRIC_DEFINITION__TYPE);
+    createEReference(externMetricDefinitionEClass, EXTERN_METRIC_DEFINITION__HEAD);
-    booleanSymbolEClass = createEClass(BOOLEAN_SYMBOL);
+    expressionEClass = createEClass(EXPRESSION);
-    integerSymbolEClass = createEClass(INTEGER_SYMBOL);
+    ifElseEClass = createEClass(IF_ELSE);
+    createEReference(ifElseEClass, IF_ELSE__CONDITION);
+    createEReference(ifElseEClass, IF_ELSE__THEN);
+    createEReference(ifElseEClass, IF_ELSE__ELSE);
-    realSymbolEClass = createEClass(REAL_SYMBOL);
+    caseEClass = createEClass(CASE);
+    createEReference(caseEClass, CASE__CONDITION);
+    createEReference(caseEClass, CASE__BODY);
-    stringSymbolEClass = createEClass(STRING_SYMBOL);
+    countEClass = createEClass(COUNT);
+    createEReference(countEClass, COUNT__BODY);
-    complexObjectEClass = createEClass(COMPLEX_OBJECT);
+    aggregationEClass = createEClass(AGGREGATION);
+    createEAttribute(aggregationEClass, AGGREGATION__OP);
+    createEReference(aggregationEClass, AGGREGATION__BODY);
+    createEReference(aggregationEClass, AGGREGATION__CONDITION);
-    objectEClass = createEClass(OBJECT);
+    callEClass = createEClass(CALL);
+    createEReference(callEClass, CALL__FUNCTOR);
+    createEReference(callEClass, CALL__ARGUMENT_LIST);
+    createEAttribute(callEClass, CALL__TRANSITIVE_CLOSURE);
+    createEAttribute(callEClass, CALL__REFLEXIVE_TRANSITIVE_CLOSURE);
-    namedObjectEClass = createEClass(NAMED_OBJECT);
+    argumentListEClass = createEClass(ARGUMENT_LIST);
-    createEAttribute(namedObjectEClass, NAMED_OBJECT__NAME);
+    createEReference(argumentListEClass, ARGUMENT_LIST__ARGUMENTS);
-    unnamedObjectEClass = createEClass(UNNAMED_OBJECT);
+    argumentEClass = createEClass(ARGUMENT);
-    createEAttribute(unnamedObjectEClass, UNNAMED_OBJECT__NAME);
-    dataObjectEClass = createEClass(DATA_OBJECT);
+    expressionArgumentEClass = createEClass(EXPRESSION_ARGUMENT);
+    createEReference(expressionArgumentEClass, EXPRESSION_ARGUMENT__BODY);
-    booleanObjectEClass = createEClass(BOOLEAN_OBJECT);
+    starArgumentEClass = createEClass(STAR_ARGUMENT);
-    createEReference(booleanObjectEClass, BOOLEAN_OBJECT__VALUE);
-    intObjectEClass = createEClass(INT_OBJECT);
+    typedArgumentEClass = createEClass(TYPED_ARGUMENT);
-    createEAttribute(intObjectEClass, INT_OBJECT__VALUE);
+    createEReference(typedArgumentEClass, TYPED_ARGUMENT__TYPE);
+    createEReference(typedArgumentEClass, TYPED_ARGUMENT__VARIABLE);
-    realObjectEClass = createEClass(REAL_OBJECT);
+    typedStarArgumentEClass = createEClass(TYPED_STAR_ARGUMENT);
-    createEAttribute(realObjectEClass, REAL_OBJECT__VALUE);
+    createEReference(typedStarArgumentEClass, TYPED_STAR_ARGUMENT__TYPE);
-    stringObjectEClass = createEClass(STRING_OBJECT);
+    referenceEClass = createEClass(REFERENCE);
-    createEAttribute(stringObjectEClass, STRING_OBJECT__VALUE);
+    createEReference(referenceEClass, REFERENCE__REFERRED);
-    predicateEClass = createEClass(PREDICATE);
+    intervalEClass = createEClass(INTERVAL);
-    createEAttribute(predicateEClass, PREDICATE__IS_ERROR);
+    createEReference(intervalEClass, INTERVAL__LOWER_BOUND);
-    createEReference(predicateEClass, PREDICATE__SYMBOL);
+    createEReference(intervalEClass, INTERVAL__UPPER_BOUND);
-    createEReference(predicateEClass, PREDICATE__PARAMETERS);
-    createEReference(predicateEClass, PREDICATE__BODIES);
-    parameterEClass = createEClass(PARAMETER);
+    literalEClass = createEClass(LITERAL);
-    createEReference(parameterEClass, PARAMETER__VARIABLE);
-    createEReference(parameterEClass, PARAMETER__TYPE);
-    patternBodyEClass = createEClass(PATTERN_BODY);
-    createEReference(patternBodyEClass, PATTERN_BODY__CONSTRAINTS);
-    polarityEClass = createEClass(POLARITY);
+    logicLiteralEClass = createEClass(LOGIC_LITERAL);
+    createEAttribute(logicLiteralEClass, LOGIC_LITERAL__VALUE);
-    constraintEClass = createEClass(CONSTRAINT);
+    numericLiteralEClass = createEClass(NUMERIC_LITERAL);
-    createEReference(constraintEClass, CONSTRAINT__POLARITY);
+    createEAttribute(numericLiteralEClass, NUMERIC_LITERAL__VALUE);
-    createEReference(constraintEClass, CONSTRAINT__SYMBOL);
-    createEReference(constraintEClass, CONSTRAINT__PARAMS);
-    createEReference(constraintEClass, CONSTRAINT__CLOSURE_TYPE);
-    closureTypeEClass = createEClass(CLOSURE_TYPE);
+    infinityLiteralEClass = createEClass(INFINITY_LITERAL);
-    literalEClass = createEClass(LITERAL);
+    emptyIntervalLiteralEClass = createEClass(EMPTY_INTERVAL_LITERAL);
-    variableEClass = createEClass(VARIABLE);
+    stringLiteralEClass = createEClass(STRING_LITERAL);
-    createEAttribute(variableEClass, VARIABLE__NAME);
+    createEAttribute(stringLiteralEClass, STRING_LITERAL__VALUE);
-    allInstancesEClass = createEClass(ALL_INSTANCES);
+    memberDefinitionEClass = createEClass(MEMBER_DEFINITION);
-    createEReference(allInstancesEClass, ALL_INSTANCES__SYMBOL);
+    createEAttribute(memberDefinitionEClass, MEMBER_DEFINITION__CONTAINMENT);
+    createEReference(memberDefinitionEClass, MEMBER_DEFINITION__TYPE);
+    createEReference(memberDefinitionEClass, MEMBER_DEFINITION__MULTIPLICITY);
+    createEAttribute(memberDefinitionEClass, MEMBER_DEFINITION__NAME);
+    createEReference(memberDefinitionEClass, MEMBER_DEFINITION__OPPOSITE);
-    allObjectsEClass = createEClass(ALL_OBJECTS);
+    multiplicityEClass = createEClass(MULTIPLICITY);
-    defaultInterpretationEClass = createEClass(DEFAULT_INTERPRETATION);
+    manyMultiplicityEClass = createEClass(MANY_MULTIPLICITY);
-    createEReference(defaultInterpretationEClass, DEFAULT_INTERPRETATION__INTERPRETATION);
-    cdInterpretationEClass = createEClass(CD_INTERPRETATION);
+    exactMultiplicityEClass = createEClass(EXACT_MULTIPLICITY);
+    createEAttribute(exactMultiplicityEClass, EXACT_MULTIPLICITY__MULTIPLICITY);
-    classInterpretationEClass = createEClass(CLASS_INTERPRETATION);
+    boundedMultiplicityEClass = createEClass(BOUNDED_MULTIPLICITY);
-    createEAttribute(classInterpretationEClass, CLASS_INTERPRETATION__ABSTRACT);
+    createEAttribute(boundedMultiplicityEClass, BOUNDED_MULTIPLICITY__LOWER_BOUND);
-    createEReference(classInterpretationEClass, CLASS_INTERPRETATION__SYMBOL);
+    createEAttribute(boundedMultiplicityEClass, BOUNDED_MULTIPLICITY__UPPER_BOUND);
-    createEReference(classInterpretationEClass, CLASS_INTERPRETATION__SUPERTYPES);
-    createEReference(classInterpretationEClass, CLASS_INTERPRETATION__FIELT);
-    enumInterpretationEClass = createEClass(ENUM_INTERPRETATION);
+    scopeDefinitionEClass = createEClass(SCOPE_DEFINITION);
-    createEReference(enumInterpretationEClass, ENUM_INTERPRETATION__SYMBOL);
+    createEReference(scopeDefinitionEClass, SCOPE_DEFINITION__TYPE);
-    createEReference(enumInterpretationEClass, ENUM_INTERPRETATION__OBJECTS);
-    fieldRelationInterpretationEClass = createEClass(FIELD_RELATION_INTERPRETATION);
+    exactScopeDefinitionEClass = createEClass(EXACT_SCOPE_DEFINITION);
-    createEAttribute(fieldRelationInterpretationEClass, FIELD_RELATION_INTERPRETATION__CONTAINMENT);
+    createEAttribute(exactScopeDefinitionEClass, EXACT_SCOPE_DEFINITION__EXACT_SCOPE);
-    createEReference(fieldRelationInterpretationEClass, FIELD_RELATION_INTERPRETATION__SYMBOL);
-    createEReference(fieldRelationInterpretationEClass, FIELD_RELATION_INTERPRETATION__MULTIPLICITY);
-    createEReference(fieldRelationInterpretationEClass, FIELD_RELATION_INTERPRETATION__TARGET);
-    globalRelationInterpretationEClass = createEClass(GLOBAL_RELATION_INTERPRETATION);
+    boundedScopeDefinitionEClass = createEClass(BOUNDED_SCOPE_DEFINITION);
-    createEAttribute(globalRelationInterpretationEClass, GLOBAL_RELATION_INTERPRETATION__CONTAINMENT);
+    createEAttribute(boundedScopeDefinitionEClass, BOUNDED_SCOPE_DEFINITION__LOWER_BOUND);
-    createEReference(globalRelationInterpretationEClass, GLOBAL_RELATION_INTERPRETATION__SYMBOL);
+    createEAttribute(boundedScopeDefinitionEClass, BOUNDED_SCOPE_DEFINITION__UPPER_BOUND);
-    createEReference(globalRelationInterpretationEClass, GLOBAL_RELATION_INTERPRETATION__SOURCE_MULTIPLICITY);
-    createEReference(globalRelationInterpretationEClass, GLOBAL_RELATION_INTERPRETATION__SOURCE);
-    createEReference(globalRelationInterpretationEClass, GLOBAL_RELATION_INTERPRETATION__TARGET_MULTIPLICITY);
-    createEReference(globalRelationInterpretationEClass, GLOBAL_RELATION_INTERPRETATION__TARGET);
-    multiplicityDefinitionEClass = createEClass(MULTIPLICITY_DEFINITION);
+    lowerBoundedScopeDefinitionEClass = createEClass(LOWER_BOUNDED_SCOPE_DEFINITION);
-    createEAttribute(multiplicityDefinitionEClass, MULTIPLICITY_DEFINITION__LOWER);
+    createEAttribute(lowerBoundedScopeDefinitionEClass, LOWER_BOUNDED_SCOPE_DEFINITION__LOWER_BOUND);
-    createEAttribute(multiplicityDefinitionEClass, MULTIPLICITY_DEFINITION__UPPER);
-    createEAttribute(multiplicityDefinitionEClass, MULTIPLICITY_DEFINITION__UNLIMITED_UPPER);
-    booleanTrueEClass = createEClass(BOOLEAN_TRUE);
+    objectiveDefinitionEClass = createEClass(OBJECTIVE_DEFINITION);
+    createEAttribute(objectiveDefinitionEClass, OBJECTIVE_DEFINITION__KIND);
+    createEReference(objectiveDefinitionEClass, OBJECTIVE_DEFINITION__OBJECTIVE);
-    booleanFalseEClass = createEClass(BOOLEAN_FALSE);
+    namedElementEClass = createEClass(NAMED_ELEMENT);
+    createEAttribute(namedElementEClass, NAMED_ELEMENT__NAME);
-    trueEClass = createEClass(TRUE);
+    assertionEClass = createEClass(ASSERTION);
+    createEReference(assertionEClass, ASSERTION__BODY);
+    createEReference(assertionEClass, ASSERTION__RANGE);
-    falseEClass = createEClass(FALSE);
+    disjunctionEClass = createEClass(DISJUNCTION);
+    createEReference(disjunctionEClass, DISJUNCTION__CHILDREN);
-    unknownEClass = createEClass(UNKNOWN);
+    switchEClass = createEClass(SWITCH);
+    createEReference(switchEClass, SWITCH__CASES);
-    errorEClass = createEClass(ERROR);
+    conjunctionEClass = createEClass(CONJUNCTION);
+    createEReference(conjunctionEClass, CONJUNCTION__CHILDREN);
-    positiveEClass = createEClass(POSITIVE);
+    comparisonEClass = createEClass(COMPARISON);
+    createEReference(comparisonEClass, COMPARISON__LEFT);
+    createEAttribute(comparisonEClass, COMPARISON__OP);
+    createEReference(comparisonEClass, COMPARISON__RIGHT);
-    negativeEClass = createEClass(NEGATIVE);
+    binaryExpressionEClass = createEClass(BINARY_EXPRESSION);
+    createEReference(binaryExpressionEClass, BINARY_EXPRESSION__LEFT);
+    createEAttribute(binaryExpressionEClass, BINARY_EXPRESSION__OP);
+    createEReference(binaryExpressionEClass, BINARY_EXPRESSION__RIGHT);
-    reflexiveClosureEClass = createEClass(REFLEXIVE_CLOSURE);
+    unaryExpressionEClass = createEClass(UNARY_EXPRESSION);
+    createEAttribute(unaryExpressionEClass, UNARY_EXPRESSION__OP);
+    createEReference(unaryExpressionEClass, UNARY_EXPRESSION__BODY);
-    irreflexiveClosureEClass = createEClass(IRREFLEXIVE_CLOSURE);
+    // Create enums
+    metricTypeEEnum = createEEnum(METRIC_TYPE);
+    binaryOperatorEEnum = createEEnum(BINARY_OPERATOR);
+    unaryOpEEnum = createEEnum(UNARY_OP);
+    aggregationOpEEnum = createEEnum(AGGREGATION_OP);
+    logicValueEEnum = createEEnum(LOGIC_VALUE);
+    objectiveKindEEnum = createEEnum(OBJECTIVE_KIND);
  }
  /**
@@ -1763,195 +2098,255 @@ public class SolverLanguagePackageImpl extends EPackageImpl implements SolverLan
    // Set bounds for type parameters
    // Add supertypes to classes
-    interpretationEClass.getESuperTypes().add(this.getStatement());
+    predicateDefinitionEClass.getESuperTypes().add(this.getStatement());
-    basicInterpretationEClass.getESuperTypes().add(this.getInterpretation());
+    unnamedErrorPrediateDefinitionEClass.getESuperTypes().add(this.getStatement());
-    modelSymbolEClass.getESuperTypes().add(this.getSymbol());
+    defaultDefinitionEClass.getESuperTypes().add(this.getStatement());
-    partialitySymbolEClass.getESuperTypes().add(this.getSymbol());
+    externPredicateDefinitionEClass.getESuperTypes().add(this.getStatement());
-    existSymbolEClass.getESuperTypes().add(this.getPartialitySymbol());
+    metricDefinitionEClass.getESuperTypes().add(this.getStatement());
-    equalsSymbolEClass.getESuperTypes().add(this.getPartialitySymbol());
+    externMetricDefinitionEClass.getESuperTypes().add(this.getStatement());
-    dataSymbolEClass.getESuperTypes().add(this.getSymbol());
+    expressionEClass.getESuperTypes().add(this.getStatement());
-    booleanSymbolEClass.getESuperTypes().add(this.getDataSymbol());
+    ifElseEClass.getESuperTypes().add(this.getExpression());
-    integerSymbolEClass.getESuperTypes().add(this.getDataSymbol());
+    caseEClass.getESuperTypes().add(this.getExpression());
-    realSymbolEClass.getESuperTypes().add(this.getDataSymbol());
+    countEClass.getESuperTypes().add(this.getExpression());
-    stringSymbolEClass.getESuperTypes().add(this.getDataSymbol());
+    aggregationEClass.getESuperTypes().add(this.getExpression());
-    objectEClass.getESuperTypes().add(this.getComplexObject());
+    callEClass.getESuperTypes().add(this.getExpression());
-    namedObjectEClass.getESuperTypes().add(this.getObject());
+    expressionArgumentEClass.getESuperTypes().add(this.getArgument());
-    namedObjectEClass.getESuperTypes().add(this.getLiteral());
+    starArgumentEClass.getESuperTypes().add(this.getArgument());
-    unnamedObjectEClass.getESuperTypes().add(this.getObject());
+    typedArgumentEClass.getESuperTypes().add(this.getArgument());
-    dataObjectEClass.getESuperTypes().add(this.getObject());
+    typedStarArgumentEClass.getESuperTypes().add(this.getArgument());
-    dataObjectEClass.getESuperTypes().add(this.getLiteral());
+    referenceEClass.getESuperTypes().add(this.getExpression());
-    booleanObjectEClass.getESuperTypes().add(this.getDataObject());
+    intervalEClass.getESuperTypes().add(this.getExpression());
-    intObjectEClass.getESuperTypes().add(this.getDataObject());
+    literalEClass.getESuperTypes().add(this.getExpression());
-    realObjectEClass.getESuperTypes().add(this.getDataObject());
+    logicLiteralEClass.getESuperTypes().add(this.getLiteral());
-    stringObjectEClass.getESuperTypes().add(this.getDataObject());
+    numericLiteralEClass.getESuperTypes().add(this.getLiteral());
-    predicateEClass.getESuperTypes().add(this.getStatement());
+    infinityLiteralEClass.getESuperTypes().add(this.getLiteral());
-    variableEClass.getESuperTypes().add(this.getLiteral());
+    emptyIntervalLiteralEClass.getESuperTypes().add(this.getLiteral());
-    allInstancesEClass.getESuperTypes().add(this.getComplexObject());
+    stringLiteralEClass.getESuperTypes().add(this.getLiteral());
-    allObjectsEClass.getESuperTypes().add(this.getComplexObject());
+    manyMultiplicityEClass.getESuperTypes().add(this.getMultiplicity());
-    defaultInterpretationEClass.getESuperTypes().add(this.getInterpretation());
+    exactMultiplicityEClass.getESuperTypes().add(this.getMultiplicity());
-    cdInterpretationEClass.getESuperTypes().add(this.getInterpretation());
+    boundedMultiplicityEClass.getESuperTypes().add(this.getMultiplicity());
-    classInterpretationEClass.getESuperTypes().add(this.getCDInterpretation());
+    scopeDefinitionEClass.getESuperTypes().add(this.getStatement());
-    enumInterpretationEClass.getESuperTypes().add(this.getCDInterpretation());
+    exactScopeDefinitionEClass.getESuperTypes().add(this.getScopeDefinition());
-    globalRelationInterpretationEClass.getESuperTypes().add(this.getCDInterpretation());
+    boundedScopeDefinitionEClass.getESuperTypes().add(this.getScopeDefinition());
-    booleanTrueEClass.getESuperTypes().add(this.getBooleanValue());
+    lowerBoundedScopeDefinitionEClass.getESuperTypes().add(this.getScopeDefinition());
-    booleanFalseEClass.getESuperTypes().add(this.getBooleanValue());
+    objectiveDefinitionEClass.getESuperTypes().add(this.getStatement());
-    trueEClass.getESuperTypes().add(this.getTruthValue());
+    assertionEClass.getESuperTypes().add(this.getStatement());
-    falseEClass.getESuperTypes().add(this.getTruthValue());
+    disjunctionEClass.getESuperTypes().add(this.getExpression());
-    unknownEClass.getESuperTypes().add(this.getTruthValue());
+    switchEClass.getESuperTypes().add(this.getExpression());
-    errorEClass.getESuperTypes().add(this.getTruthValue());
+    conjunctionEClass.getESuperTypes().add(this.getExpression());
-    positiveEClass.getESuperTypes().add(this.getPolarity());
+    comparisonEClass.getESuperTypes().add(this.getExpression());
-    negativeEClass.getESuperTypes().add(this.getPolarity());
+    binaryExpressionEClass.getESuperTypes().add(this.getExpression());
-    reflexiveClosureEClass.getESuperTypes().add(this.getClosureType());
+    unaryExpressionEClass.getESuperTypes().add(this.getExpression());
-    irreflexiveClosureEClass.getESuperTypes().add(this.getClosureType());
    // Initialize classes and features; add operations and parameters
    initEClass(problemEClass, Problem.class, "Problem", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
    initEReference(getProblem_Statements(), this.getStatement(), null, "statements", null, 0, -1, Problem.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
    initEClass(statementEClass, Statement.class, "Statement", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getStatement_Abstract(), ecorePackage.getEBoolean(), "abstract", null, 0, 1, Statement.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getStatement_Name(), ecorePackage.getEString(), "name", null, 0, 1, Statement.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getStatement_Superclasses(), this.getNamedElement(), null, "superclasses", null, 0, -1, Statement.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_COMPOSITE, IS_RESOLVE_PROXIES, !IS_UNSETTABLE, !IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getStatement_Members(), this.getMemberDefinition(), null, "members", null, 0, -1, Statement.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(booleanValueEClass, BooleanValue.class, "BooleanValue", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(predicateDefinitionEClass, PredicateDefinition.class, "PredicateDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getPredicateDefinition_Head(), this.getExpression(), null, "head", null, 0, 1, PredicateDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(truthValueEClass, TruthValue.class, "TruthValue", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getPredicateDefinition_Body(), this.getExpression(), null, "body", null, 0, 1, PredicateDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getPredicateDefinition_Functional(), ecorePackage.getEBoolean(), "functional", null, 0, 1, PredicateDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(interpretationEClass, Interpretation.class, "Interpretation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getPredicateDefinition_Error(), ecorePackage.getEBoolean(), "error", null, 0, 1, PredicateDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(basicInterpretationEClass, BasicInterpretation.class, "BasicInterpretation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEReference(getBasicInterpretation_Symbol(), this.getSymbol(), null, "symbol", null, 0, 1, BasicInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getBasicInterpretation_Objects(), this.getComplexObject(), null, "objects", null, 0, -1, BasicInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getBasicInterpretation_Value(), this.getTruthValue(), null, "value", null, 0, 1, BasicInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(symbolEClass, Symbol.class, "Symbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(modelSymbolEClass, ModelSymbol.class, "ModelSymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getModelSymbol_Name(), ecorePackage.getEString(), "name", null, 0, 1, ModelSymbol.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(partialitySymbolEClass, PartialitySymbol.class, "PartialitySymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(existSymbolEClass, ExistSymbol.class, "ExistSymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(unnamedErrorPrediateDefinitionEClass, UnnamedErrorPrediateDefinition.class, "UnnamedErrorPrediateDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getUnnamedErrorPrediateDefinition_ArgumentList(), this.getArgumentList(), null, "argumentList", null, 0, 1, UnnamedErrorPrediateDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getUnnamedErrorPrediateDefinition_Body(), this.getExpression(), null, "body", null, 0, 1, UnnamedErrorPrediateDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(equalsSymbolEClass, EqualsSymbol.class, "EqualsSymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(defaultDefinitionEClass, DefaultDefinition.class, "DefaultDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getDefaultDefinition_Head(), this.getCall(), null, "head", null, 0, 1, DefaultDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getDefaultDefinition_Range(), this.getExpression(), null, "range", null, 0, 1, DefaultDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(dataSymbolEClass, DataSymbol.class, "DataSymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(externPredicateDefinitionEClass, ExternPredicateDefinition.class, "ExternPredicateDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getExternPredicateDefinition_Head(), this.getCall(), null, "head", null, 0, 1, ExternPredicateDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(booleanSymbolEClass, BooleanSymbol.class, "BooleanSymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(metricDefinitionEClass, MetricDefinition.class, "MetricDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getMetricDefinition_Head(), this.getExpression(), null, "head", null, 0, 1, MetricDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getMetricDefinition_Body(), this.getExpression(), null, "body", null, 0, 1, MetricDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getMetricDefinition_Type(), this.getMetricType(), "type", null, 0, 1, MetricDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(integerSymbolEClass, IntegerSymbol.class, "IntegerSymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(externMetricDefinitionEClass, ExternMetricDefinition.class, "ExternMetricDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getExternMetricDefinition_Type(), this.getMetricType(), "type", null, 0, 1, ExternMetricDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getExternMetricDefinition_Head(), this.getCall(), null, "head", null, 0, 1, ExternMetricDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(realSymbolEClass, RealSymbol.class, "RealSymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(expressionEClass, Expression.class, "Expression", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(stringSymbolEClass, StringSymbol.class, "StringSymbol", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(ifElseEClass, IfElse.class, "IfElse", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getIfElse_Condition(), this.getExpression(), null, "condition", null, 0, 1, IfElse.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getIfElse_Then(), this.getExpression(), null, "then", null, 0, 1, IfElse.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getIfElse_Else(), this.getExpression(), null, "else", null, 0, 1, IfElse.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(complexObjectEClass, ComplexObject.class, "ComplexObject", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(caseEClass, Case.class, "Case", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getCase_Condition(), this.getExpression(), null, "condition", null, 0, 1, Case.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getCase_Body(), this.getExpression(), null, "body", null, 0, 1, Case.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(objectEClass, org.eclipse.viatra.solver.language.solverLanguage.Object.class, "Object", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(countEClass, Count.class, "Count", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getCount_Body(), this.getExpression(), null, "body", null, 0, 1, Count.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(namedObjectEClass, NamedObject.class, "NamedObject", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(aggregationEClass, Aggregation.class, "Aggregation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getNamedObject_Name(), ecorePackage.getEString(), "name", null, 0, 1, NamedObject.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getAggregation_Op(), this.getAggregationOp(), "op", null, 0, 1, Aggregation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getAggregation_Body(), this.getExpression(), null, "body", null, 0, 1, Aggregation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getAggregation_Condition(), this.getExpression(), null, "condition", null, 0, 1, Aggregation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(unnamedObjectEClass, UnnamedObject.class, "UnnamedObject", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(callEClass, Call.class, "Call", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getUnnamedObject_Name(), ecorePackage.getEString(), "name", null, 0, 1, UnnamedObject.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getCall_Functor(), this.getReference(), null, "functor", null, 0, 1, Call.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getCall_ArgumentList(), this.getArgumentList(), null, "argumentList", null, 0, 1, Call.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getCall_TransitiveClosure(), ecorePackage.getEBoolean(), "transitiveClosure", null, 0, 1, Call.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getCall_ReflexiveTransitiveClosure(), ecorePackage.getEBoolean(), "reflexiveTransitiveClosure", null, 0, 1, Call.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(dataObjectEClass, DataObject.class, "DataObject", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(argumentListEClass, ArgumentList.class, "ArgumentList", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getArgumentList_Arguments(), this.getArgument(), null, "arguments", null, 0, -1, ArgumentList.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(booleanObjectEClass, BooleanObject.class, "BooleanObject", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(argumentEClass, Argument.class, "Argument", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEReference(getBooleanObject_Value(), this.getBooleanValue(), null, "value", null, 0, 1, BooleanObject.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(intObjectEClass, IntObject.class, "IntObject", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(expressionArgumentEClass, ExpressionArgument.class, "ExpressionArgument", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getIntObject_Value(), ecorePackage.getEInt(), "value", null, 0, 1, IntObject.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getExpressionArgument_Body(), this.getExpression(), null, "body", null, 0, 1, ExpressionArgument.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(realObjectEClass, RealObject.class, "RealObject", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(starArgumentEClass, StarArgument.class, "StarArgument", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getRealObject_Value(), ecorePackage.getEBigDecimal(), "value", null, 0, 1, RealObject.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(stringObjectEClass, StringObject.class, "StringObject", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(typedArgumentEClass, TypedArgument.class, "TypedArgument", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getStringObject_Value(), ecorePackage.getEString(), "value", null, 0, 1, StringObject.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getTypedArgument_Type(), this.getNamedElement(), null, "type", null, 0, 1, TypedArgument.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_COMPOSITE, IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getTypedArgument_Variable(), this.getNamedElement(), null, "variable", null, 0, 1, TypedArgument.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_COMPOSITE, IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(predicateEClass, Predicate.class, "Predicate", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(typedStarArgumentEClass, TypedStarArgument.class, "TypedStarArgument", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getPredicate_IsError(), ecorePackage.getEBoolean(), "isError", null, 0, 1, Predicate.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getTypedStarArgument_Type(), this.getNamedElement(), null, "type", null, 0, 1, TypedStarArgument.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_COMPOSITE, IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getPredicate_Symbol(), this.getModelSymbol(), null, "symbol", null, 0, 1, Predicate.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getPredicate_Parameters(), this.getParameter(), null, "parameters", null, 0, -1, Predicate.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getPredicate_Bodies(), this.getPatternBody(), null, "bodies", null, 0, -1, Predicate.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(parameterEClass, Parameter.class, "Parameter", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(referenceEClass, Reference.class, "Reference", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEReference(getParameter_Variable(), this.getVariable(), null, "variable", null, 0, 1, Parameter.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getReference_Referred(), this.getNamedElement(), null, "referred", null, 0, 1, Reference.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_COMPOSITE, IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getParameter_Type(), this.getSymbol(), null, "type", null, 0, 1, Parameter.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(patternBodyEClass, PatternBody.class, "PatternBody", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(intervalEClass, Interval.class, "Interval", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEReference(getPatternBody_Constraints(), this.getConstraint(), null, "constraints", null, 0, -1, PatternBody.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getInterval_LowerBound(), this.getExpression(), null, "lowerBound", null, 0, 1, Interval.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getInterval_UpperBound(), this.getExpression(), null, "upperBound", null, 0, 1, Interval.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(polarityEClass, Polarity.class, "Polarity", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(constraintEClass, Constraint.class, "Constraint", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEReference(getConstraint_Polarity(), this.getPolarity(), null, "polarity", null, 0, 1, Constraint.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getConstraint_Symbol(), this.getModelSymbol(), null, "symbol", null, 0, 1, Constraint.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getConstraint_Params(), this.getLiteral(), null, "params", null, 0, -1, Constraint.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getConstraint_ClosureType(), this.getClosureType(), null, "closureType", null, 0, 1, Constraint.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(closureTypeEClass, ClosureType.class, "ClosureType", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
    initEClass(literalEClass, Literal.class, "Literal", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(variableEClass, Variable.class, "Variable", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(logicLiteralEClass, LogicLiteral.class, "LogicLiteral", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getVariable_Name(), ecorePackage.getEString(), "name", null, 0, 1, Variable.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getLogicLiteral_Value(), this.getLogicValue(), "value", null, 0, 1, LogicLiteral.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(allInstancesEClass, AllInstances.class, "AllInstances", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEReference(getAllInstances_Symbol(), this.getSymbol(), null, "symbol", null, 0, 1, AllInstances.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(allObjectsEClass, AllObjects.class, "AllObjects", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(defaultInterpretationEClass, DefaultInterpretation.class, "DefaultInterpretation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEReference(getDefaultInterpretation_Interpretation(), this.getBasicInterpretation(), null, "interpretation", null, 0, 1, DefaultInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(cdInterpretationEClass, CDInterpretation.class, "CDInterpretation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(classInterpretationEClass, ClassInterpretation.class, "ClassInterpretation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getClassInterpretation_Abstract(), ecorePackage.getEBoolean(), "abstract", null, 0, 1, ClassInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getClassInterpretation_Symbol(), this.getModelSymbol(), null, "symbol", null, 0, 1, ClassInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getClassInterpretation_Supertypes(), this.getModelSymbol(), null, "supertypes", null, 0, -1, ClassInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getClassInterpretation_Fielt(), this.getFieldRelationInterpretation(), null, "fielt", null, 0, -1, ClassInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(enumInterpretationEClass, EnumInterpretation.class, "EnumInterpretation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEReference(getEnumInterpretation_Symbol(), this.getModelSymbol(), null, "Symbol", null, 0, 1, EnumInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getEnumInterpretation_Objects(), this.getNamedObject(), null, "objects", null, 0, -1, EnumInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(fieldRelationInterpretationEClass, FieldRelationInterpretation.class, "FieldRelationInterpretation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getFieldRelationInterpretation_Containment(), ecorePackage.getEBoolean(), "containment", null, 0, 1, FieldRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getFieldRelationInterpretation_Symbol(), this.getModelSymbol(), null, "symbol", null, 0, 1, FieldRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getFieldRelationInterpretation_Multiplicity(), this.getMultiplicityDefinition(), null, "multiplicity", null, 0, 1, FieldRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getFieldRelationInterpretation_Target(), this.getSymbol(), null, "target", null, 0, 1, FieldRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(globalRelationInterpretationEClass, GlobalRelationInterpretation.class, "GlobalRelationInterpretation", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getGlobalRelationInterpretation_Containment(), ecorePackage.getEBoolean(), "containment", null, 0, 1, GlobalRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getGlobalRelationInterpretation_Symbol(), this.getModelSymbol(), null, "symbol", null, 0, 1, GlobalRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getGlobalRelationInterpretation_SourceMultiplicity(), this.getMultiplicityDefinition(), null, "sourceMultiplicity", null, 0, 1, GlobalRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getGlobalRelationInterpretation_Source(), this.getSymbol(), null, "source", null, 0, 1, GlobalRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getGlobalRelationInterpretation_TargetMultiplicity(), this.getMultiplicityDefinition(), null, "targetMultiplicity", null, 0, 1, GlobalRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEReference(getGlobalRelationInterpretation_Target(), this.getSymbol(), null, "target", null, 0, 1, GlobalRelationInterpretation.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(multiplicityDefinitionEClass, MultiplicityDefinition.class, "MultiplicityDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEAttribute(getMultiplicityDefinition_Lower(), ecorePackage.getEInt(), "lower", null, 0, 1, MultiplicityDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEAttribute(getMultiplicityDefinition_Upper(), ecorePackage.getEInt(), "upper", null, 0, 1, MultiplicityDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEAttribute(getMultiplicityDefinition_UnlimitedUpper(), ecorePackage.getEBoolean(), "unlimitedUpper", null, 0, 1, MultiplicityDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(booleanTrueEClass, BooleanTrue.class, "BooleanTrue", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(booleanFalseEClass, BooleanFalse.class, "BooleanFalse", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(trueEClass, True.class, "True", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(falseEClass, False.class, "False", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(unknownEClass, Unknown.class, "Unknown", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(errorEClass, org.eclipse.viatra.solver.language.solverLanguage.Error.class, "Error", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(numericLiteralEClass, NumericLiteral.class, "NumericLiteral", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getNumericLiteral_Value(), ecorePackage.getEBigDecimal(), "value", null, 0, 1, NumericLiteral.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(positiveEClass, Positive.class, "Positive", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(infinityLiteralEClass, InfinityLiteral.class, "InfinityLiteral", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(negativeEClass, Negative.class, "Negative", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(emptyIntervalLiteralEClass, EmptyIntervalLiteral.class, "EmptyIntervalLiteral", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
-    initEClass(reflexiveClosureEClass, ReflexiveClosure.class, "ReflexiveClosure", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(stringLiteralEClass, StringLiteral.class, "StringLiteral", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getStringLiteral_Value(), ecorePackage.getEString(), "value", null, 0, 1, StringLiteral.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
-    initEClass(irreflexiveClosureEClass, IrreflexiveClosure.class, "IrreflexiveClosure", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(memberDefinitionEClass, MemberDefinition.class, "MemberDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getMemberDefinition_Containment(), ecorePackage.getEBoolean(), "containment", null, 0, 1, MemberDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getMemberDefinition_Type(), this.getNamedElement(), null, "type", null, 0, 1, MemberDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_COMPOSITE, IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getMemberDefinition_Multiplicity(), this.getMultiplicity(), null, "multiplicity", null, 0, 1, MemberDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getMemberDefinition_Name(), ecorePackage.getEString(), "name", null, 0, 1, MemberDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getMemberDefinition_Opposite(), this.getNamedElement(), null, "opposite", null, 0, 1, MemberDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_COMPOSITE, IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(multiplicityEClass, Multiplicity.class, "Multiplicity", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(manyMultiplicityEClass, ManyMultiplicity.class, "ManyMultiplicity", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEClass(exactMultiplicityEClass, ExactMultiplicity.class, "ExactMultiplicity", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getExactMultiplicity_Multiplicity(), ecorePackage.getEInt(), "multiplicity", null, 0, 1, ExactMultiplicity.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(boundedMultiplicityEClass, BoundedMultiplicity.class, "BoundedMultiplicity", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getBoundedMultiplicity_LowerBound(), ecorePackage.getEInt(), "lowerBound", null, 0, 1, BoundedMultiplicity.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getBoundedMultiplicity_UpperBound(), ecorePackage.getEInt(), "upperBound", null, 0, 1, BoundedMultiplicity.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(scopeDefinitionEClass, ScopeDefinition.class, "ScopeDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getScopeDefinition_Type(), this.getNamedElement(), null, "type", null, 0, 1, ScopeDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_COMPOSITE, IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(exactScopeDefinitionEClass, ExactScopeDefinition.class, "ExactScopeDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getExactScopeDefinition_ExactScope(), ecorePackage.getEInt(), "exactScope", null, 0, 1, ExactScopeDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(boundedScopeDefinitionEClass, BoundedScopeDefinition.class, "BoundedScopeDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getBoundedScopeDefinition_LowerBound(), ecorePackage.getEInt(), "lowerBound", null, 0, 1, BoundedScopeDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getBoundedScopeDefinition_UpperBound(), ecorePackage.getEInt(), "upperBound", null, 0, 1, BoundedScopeDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(lowerBoundedScopeDefinitionEClass, LowerBoundedScopeDefinition.class, "LowerBoundedScopeDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getLowerBoundedScopeDefinition_LowerBound(), ecorePackage.getEInt(), "lowerBound", null, 0, 1, LowerBoundedScopeDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(objectiveDefinitionEClass, ObjectiveDefinition.class, "ObjectiveDefinition", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getObjectiveDefinition_Kind(), this.getObjectiveKind(), "kind", null, 0, 1, ObjectiveDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getObjectiveDefinition_Objective(), this.getExpression(), null, "objective", null, 0, 1, ObjectiveDefinition.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(namedElementEClass, NamedElement.class, "NamedElement", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getNamedElement_Name(), ecorePackage.getEString(), "name", null, 0, 1, NamedElement.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(assertionEClass, Assertion.class, "Assertion", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getAssertion_Body(), this.getExpression(), null, "body", null, 0, 1, Assertion.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getAssertion_Range(), this.getExpression(), null, "range", null, 0, 1, Assertion.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(disjunctionEClass, Disjunction.class, "Disjunction", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getDisjunction_Children(), this.getExpression(), null, "children", null, 0, -1, Disjunction.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(switchEClass, Switch.class, "Switch", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getSwitch_Cases(), this.getCase(), null, "cases", null, 0, -1, Switch.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(conjunctionEClass, Conjunction.class, "Conjunction", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getConjunction_Children(), this.getExpression(), null, "children", null, 0, -1, Conjunction.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(comparisonEClass, Comparison.class, "Comparison", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getComparison_Left(), this.getExpression(), null, "left", null, 0, 1, Comparison.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getComparison_Op(), this.getBinaryOperator(), "op", null, 0, 1, Comparison.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getComparison_Right(), this.getExpression(), null, "right", null, 0, 1, Comparison.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(binaryExpressionEClass, BinaryExpression.class, "BinaryExpression", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEReference(getBinaryExpression_Left(), this.getExpression(), null, "left", null, 0, 1, BinaryExpression.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEAttribute(getBinaryExpression_Op(), this.getBinaryOperator(), "op", null, 0, 1, BinaryExpression.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getBinaryExpression_Right(), this.getExpression(), null, "right", null, 0, 1, BinaryExpression.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEClass(unaryExpressionEClass, UnaryExpression.class, "UnaryExpression", !IS_ABSTRACT, !IS_INTERFACE, IS_GENERATED_INSTANCE_CLASS);
+    initEAttribute(getUnaryExpression_Op(), this.getUnaryOp(), "op", null, 0, 1, UnaryExpression.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, !IS_UNSETTABLE, !IS_ID, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    initEReference(getUnaryExpression_Body(), this.getExpression(), null, "body", null, 0, 1, UnaryExpression.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED);
+    // Initialize enums and add enum literals
+    initEEnum(metricTypeEEnum, MetricType.class, "MetricType");
+    addEEnumLiteral(metricTypeEEnum, MetricType.INT);
+    addEEnumLiteral(metricTypeEEnum, MetricType.REAL);
+    initEEnum(binaryOperatorEEnum, BinaryOperator.class, "BinaryOperator");
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.EQ);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.NOT_EQ);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.LESS);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.LESS_EQ);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.GREATER);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.GREATER_EQ);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.IN);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.ADD);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.SUB);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.MUL);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.DIV);
+    addEEnumLiteral(binaryOperatorEEnum, BinaryOperator.POW);
+    initEEnum(unaryOpEEnum, UnaryOp.class, "UnaryOp");
+    addEEnumLiteral(unaryOpEEnum, UnaryOp.NEG);
+    addEEnumLiteral(unaryOpEEnum, UnaryOp.PLUS);
+    addEEnumLiteral(unaryOpEEnum, UnaryOp.MINUS);
+    addEEnumLiteral(unaryOpEEnum, UnaryOp.MAY);
+    addEEnumLiteral(unaryOpEEnum, UnaryOp.MUST);
+    addEEnumLiteral(unaryOpEEnum, UnaryOp.CURRENT);
+    initEEnum(aggregationOpEEnum, AggregationOp.class, "AggregationOp");
+    addEEnumLiteral(aggregationOpEEnum, AggregationOp.ONLY);
+    addEEnumLiteral(aggregationOpEEnum, AggregationOp.SUM);
+    addEEnumLiteral(aggregationOpEEnum, AggregationOp.PROD);
+    addEEnumLiteral(aggregationOpEEnum, AggregationOp.AVG);
+    addEEnumLiteral(aggregationOpEEnum, AggregationOp.MIN);
+    addEEnumLiteral(aggregationOpEEnum, AggregationOp.MAX);
+    initEEnum(logicValueEEnum, LogicValue.class, "LogicValue");
+    addEEnumLiteral(logicValueEEnum, LogicValue.TRUE);
+    addEEnumLiteral(logicValueEEnum, LogicValue.FALSE);
+    addEEnumLiteral(logicValueEEnum, LogicValue.UNKNOWN);
+    addEEnumLiteral(logicValueEEnum, LogicValue.ERROR);
+    initEEnum(objectiveKindEEnum, ObjectiveKind.class, "ObjectiveKind");
+    addEEnumLiteral(objectiveKindEEnum, ObjectiveKind.MINIMIZE);
+    addEEnumLiteral(objectiveKindEEnum, ObjectiveKind.MAXIMIZE);
    // Create resource
    createResource(eNS_URI);
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StringSymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StarArgumentImpl.java
index faf3f06a..b0cecaab 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StringSymbolImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StarArgumentImpl.java
@@ -1,28 +1,28 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
 import org.eclipse.emf.ecore.EClass;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.StringSymbol;
+import org.eclipse.viatra.solver.language.solverLanguage.StarArgument;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>String Symbol</b></em>'.
+ * An implementation of the model object '<em><b>Star Argument</b></em>'.
 * <!-- end-user-doc -->
 *
 * @generated
 */
-public class StringSymbolImpl extends DataSymbolImpl implements StringSymbol
+public class StarArgumentImpl extends ArgumentImpl implements StarArgument
 {
  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
-  protected StringSymbolImpl()
+  protected StarArgumentImpl()
  {
    super();
  }
@@ -35,7 +35,7 @@ public class StringSymbolImpl extends DataSymbolImpl implements StringSymbol
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.STRING_SYMBOL;
+    return SolverLanguagePackage.Literals.STAR_ARGUMENT;
  }
-} //StringSymbolImpl
+} //StarArgumentImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StatementImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StatementImpl.java
index 6e660396..dbd697ec 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StatementImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StatementImpl.java
@@ -1,12 +1,27 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import java.util.Collection;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.common.util.EList;
 import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
 import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
+import org.eclipse.emf.ecore.util.EObjectContainmentEList;
+import org.eclipse.emf.ecore.util.EObjectResolvingEList;
+import org.eclipse.emf.ecore.util.InternalEList;
+import org.eclipse.viatra.solver.language.solverLanguage.MemberDefinition;
+import org.eclipse.viatra.solver.language.solverLanguage.NamedElement;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
 import org.eclipse.viatra.solver.language.solverLanguage.Statement;
@@ -14,12 +29,81 @@ import org.eclipse.viatra.solver.language.solverLanguage.Statement;
 * <!-- begin-user-doc -->
 * An implementation of the model object '<em><b>Statement</b></em>'.
 * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.StatementImpl#isAbstract <em>Abstract</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.StatementImpl#getName <em>Name</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.StatementImpl#getSuperclasses <em>Superclasses</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.StatementImpl#getMembers <em>Members</em>}</li>
+ * </ul>
 *
 * @generated
 */
 public class StatementImpl extends MinimalEObjectImpl.Container implements Statement
 {
  /**
+   * The default value of the '{@link #isAbstract() <em>Abstract</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isAbstract()
+   * @generated
+   * @ordered
+   */
+  protected static final boolean ABSTRACT_EDEFAULT = false;
+  /**
+   * The cached value of the '{@link #isAbstract() <em>Abstract</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #isAbstract()
+   * @generated
+   * @ordered
+   */
+  protected boolean abstract_ = ABSTRACT_EDEFAULT;
+  /**
+   * The default value of the '{@link #getName() <em>Name</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getName()
+   * @generated
+   * @ordered
+   */
+  protected static final String NAME_EDEFAULT = null;
+  /**
+   * The cached value of the '{@link #getName() <em>Name</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getName()
+   * @generated
+   * @ordered
+   */
+  protected String name = NAME_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getSuperclasses() <em>Superclasses</em>}' reference list.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getSuperclasses()
+   * @generated
+   * @ordered
+   */
+  protected EList<NamedElement> superclasses;
+  /**
+   * The cached value of the '{@link #getMembers() <em>Members</em>}' containment reference list.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getMembers()
+   * @generated
+   * @ordered
+   */
+  protected EList<MemberDefinition> members;
+  /**
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
@@ -40,4 +124,218 @@ public class StatementImpl extends MinimalEObjectImpl.Container implements State
    return SolverLanguagePackage.Literals.STATEMENT;
  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean isAbstract()
+  {
+    return abstract_;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setAbstract(boolean newAbstract)
+  {
+    boolean oldAbstract = abstract_;
+    abstract_ = newAbstract;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.STATEMENT__ABSTRACT, oldAbstract, abstract_));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String getName()
+  {
+    return name;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setName(String newName)
+  {
+    String oldName = name;
+    name = newName;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.STATEMENT__NAME, oldName, name));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EList<NamedElement> getSuperclasses()
+  {
+    if (superclasses == null)
+    {
+      superclasses = new EObjectResolvingEList<NamedElement>(NamedElement.class, this, SolverLanguagePackage.STATEMENT__SUPERCLASSES);
+    }
+    return superclasses;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EList<MemberDefinition> getMembers()
+  {
+    if (members == null)
+    {
+      members = new EObjectContainmentEList<MemberDefinition>(MemberDefinition.class, this, SolverLanguagePackage.STATEMENT__MEMBERS);
+    }
+    return members;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.STATEMENT__MEMBERS:
+        return ((InternalEList<?>)getMembers()).basicRemove(otherEnd, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.STATEMENT__ABSTRACT:
+        return isAbstract();
+      case SolverLanguagePackage.STATEMENT__NAME:
+        return getName();
+      case SolverLanguagePackage.STATEMENT__SUPERCLASSES:
+        return getSuperclasses();
+      case SolverLanguagePackage.STATEMENT__MEMBERS:
+        return getMembers();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @SuppressWarnings("unchecked")
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.STATEMENT__ABSTRACT:
+        setAbstract((Boolean)newValue);
+        return;
+      case SolverLanguagePackage.STATEMENT__NAME:
+        setName((String)newValue);
+        return;
+      case SolverLanguagePackage.STATEMENT__SUPERCLASSES:
+        getSuperclasses().clear();
+        getSuperclasses().addAll((Collection<? extends NamedElement>)newValue);
+        return;
+      case SolverLanguagePackage.STATEMENT__MEMBERS:
+        getMembers().clear();
+        getMembers().addAll((Collection<? extends MemberDefinition>)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.STATEMENT__ABSTRACT:
+        setAbstract(ABSTRACT_EDEFAULT);
+        return;
+      case SolverLanguagePackage.STATEMENT__NAME:
+        setName(NAME_EDEFAULT);
+        return;
+      case SolverLanguagePackage.STATEMENT__SUPERCLASSES:
+        getSuperclasses().clear();
+        return;
+      case SolverLanguagePackage.STATEMENT__MEMBERS:
+        getMembers().clear();
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.STATEMENT__ABSTRACT:
+        return abstract_ != ABSTRACT_EDEFAULT;
+      case SolverLanguagePackage.STATEMENT__NAME:
+        return NAME_EDEFAULT == null ? name != null : !NAME_EDEFAULT.equals(name);
+      case SolverLanguagePackage.STATEMENT__SUPERCLASSES:
+        return superclasses != null && !superclasses.isEmpty();
+      case SolverLanguagePackage.STATEMENT__MEMBERS:
+        return members != null && !members.isEmpty();
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (abstract: ");
+    result.append(abstract_);
+    result.append(", name: ");
+    result.append(name);
+    result.append(')');
+    return result.toString();
+  }
 } //StatementImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StringObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StringLiteralImpl.java
index 7a7866a7..2b0b2720 100644
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StringObjectImpl.java
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/StringLiteralImpl.java
@@ -1,5 +1,5 @@
 /**
- * generated by Xtext 2.18.0.M3
+ * generated by Xtext 2.21.0
 */
 package org.eclipse.viatra.solver.language.solverLanguage.impl;
@@ -10,22 +10,22 @@ import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
 import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.StringObject;
+import org.eclipse.viatra.solver.language.solverLanguage.StringLiteral;
 /**
 * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>String Object</b></em>'.
+ * An implementation of the model object '<em><b>String Literal</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * </p>
 * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.StringObjectImpl#getValue <em>Value</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.StringLiteralImpl#getValue <em>Value</em>}</li>
 * </ul>
 *
 * @generated
 */
-public class StringObjectImpl extends DataObjectImpl implements StringObject
+public class StringLiteralImpl extends LiteralImpl implements StringLiteral
 {
  /**
   * The default value of the '{@link #getValue() <em>Value</em>}' attribute.
@@ -52,7 +52,7 @@ public class StringObjectImpl extends DataObjectImpl implements StringObject
   * <!-- end-user-doc -->
   * @generated
   */
-  protected StringObjectImpl()
+  protected StringLiteralImpl()
  {
    super();
  }
@@ -65,7 +65,7 @@ public class StringObjectImpl extends DataObjectImpl implements StringObject
  @Override
  protected EClass eStaticClass()
  {
-    return SolverLanguagePackage.Literals.STRING_OBJECT;
+    return SolverLanguagePackage.Literals.STRING_LITERAL;
  }
  /**
@@ -90,7 +90,7 @@ public class StringObjectImpl extends DataObjectImpl implements StringObject
    String oldValue = value;
    value = newValue;
    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.STRING_OBJECT__VALUE, oldValue, value));
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.STRING_LITERAL__VALUE, oldValue, value));
  }
  /**
@@ -103,7 +103,7 @@ public class StringObjectImpl extends DataObjectImpl implements StringObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.STRING_OBJECT__VALUE:
+      case SolverLanguagePackage.STRING_LITERAL__VALUE:
        return getValue();
    }
    return super.eGet(featureID, resolve, coreType);
@@ -119,7 +119,7 @@ public class StringObjectImpl extends DataObjectImpl implements StringObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.STRING_OBJECT__VALUE:
+      case SolverLanguagePackage.STRING_LITERAL__VALUE:
        setValue((String)newValue);
        return;
    }
@@ -136,7 +136,7 @@ public class StringObjectImpl extends DataObjectImpl implements StringObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.STRING_OBJECT__VALUE:
+      case SolverLanguagePackage.STRING_LITERAL__VALUE:
        setValue(VALUE_EDEFAULT);
        return;
    }
@@ -153,7 +153,7 @@ public class StringObjectImpl extends DataObjectImpl implements StringObject
  {
    switch (featureID)
    {
-      case SolverLanguagePackage.STRING_OBJECT__VALUE:
+      case SolverLanguagePackage.STRING_LITERAL__VALUE:
        return VALUE_EDEFAULT == null ? value != null : !VALUE_EDEFAULT.equals(value);
    }
    return super.eIsSet(featureID);
@@ -176,4 +176,4 @@ public class StringObjectImpl extends DataObjectImpl implements StringObject
    return result.toString();
  }
-} //StringObjectImpl
+} //StringLiteralImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SwitchImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SwitchImpl.java
new file mode 100644
index 00000000..fefd5be6
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SwitchImpl.java
@@ -0,0 +1,167 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import java.util.Collection;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.common.util.EList;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.util.EObjectContainmentEList;
+import org.eclipse.emf.ecore.util.InternalEList;
+import org.eclipse.viatra.solver.language.solverLanguage.Case;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+import org.eclipse.viatra.solver.language.solverLanguage.Switch;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Switch</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.SwitchImpl#getCases <em>Cases</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class SwitchImpl extends ExpressionImpl implements Switch
+{
+  /**
+   * The cached value of the '{@link #getCases() <em>Cases</em>}' containment reference list.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getCases()
+   * @generated
+   * @ordered
+   */
+  protected EList<Case> cases;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected SwitchImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.SWITCH;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public EList<Case> getCases()
+  {
+    if (cases == null)
+    {
+      cases = new EObjectContainmentEList<Case>(Case.class, this, SolverLanguagePackage.SWITCH__CASES);
+    }
+    return cases;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SWITCH__CASES:
+        return ((InternalEList<?>)getCases()).basicRemove(otherEnd, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SWITCH__CASES:
+        return getCases();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @SuppressWarnings("unchecked")
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SWITCH__CASES:
+        getCases().clear();
+        getCases().addAll((Collection<? extends Case>)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SWITCH__CASES:
+        getCases().clear();
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.SWITCH__CASES:
+        return cases != null && !cases.isEmpty();
+    }
+    return super.eIsSet(featureID);
+  }
+} //SwitchImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SymbolImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SymbolImpl.java
deleted file mode 100644
index 15d1294e..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/SymbolImpl.java
+++ /dev/null
@@ -1,43 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.Symbol;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Symbol</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class SymbolImpl extends MinimalEObjectImpl.Container implements Symbol
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected SymbolImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.SYMBOL;
-  }
-} //SymbolImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TrueImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TrueImpl.java
deleted file mode 100644
index c0e04a9a..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TrueImpl.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.True;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>True</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class TrueImpl extends TruthValueImpl implements True
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected TrueImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.TRUE;
-  }
-} //TrueImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TruthValueImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TruthValueImpl.java
deleted file mode 100644
index f5b0fba6..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TruthValueImpl.java
+++ /dev/null
@@ -1,43 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.TruthValue;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Truth Value</b></em>'.
- * <!-- end-user-doc -->
- *
- * @generated
- */
-public class TruthValueImpl extends MinimalEObjectImpl.Container implements TruthValue
-{
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected TruthValueImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.TRUTH_VALUE;
-  }
-} //TruthValueImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TypedArgumentImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TypedArgumentImpl.java
new file mode 100644
index 00000000..2d93f402
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TypedArgumentImpl.java
@@ -0,0 +1,242 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.NamedElement;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+import org.eclipse.viatra.solver.language.solverLanguage.TypedArgument;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Typed Argument</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.TypedArgumentImpl#getType <em>Type</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.TypedArgumentImpl#getVariable <em>Variable</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class TypedArgumentImpl extends ArgumentImpl implements TypedArgument
+{
+  /**
+   * The cached value of the '{@link #getType() <em>Type</em>}' reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getType()
+   * @generated
+   * @ordered
+   */
+  protected NamedElement type;
+  /**
+   * The cached value of the '{@link #getVariable() <em>Variable</em>}' reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getVariable()
+   * @generated
+   * @ordered
+   */
+  protected NamedElement variable;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected TypedArgumentImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.TYPED_ARGUMENT;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NamedElement getType()
+  {
+    if (type != null && type.eIsProxy())
+    {
+      InternalEObject oldType = (InternalEObject)type;
+      type = (NamedElement)eResolveProxy(oldType);
+      if (type != oldType)
+      {
+        if (eNotificationRequired())
+          eNotify(new ENotificationImpl(this, Notification.RESOLVE, SolverLanguagePackage.TYPED_ARGUMENT__TYPE, oldType, type));
+      }
+    }
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NamedElement basicGetType()
+  {
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setType(NamedElement newType)
+  {
+    NamedElement oldType = type;
+    type = newType;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.TYPED_ARGUMENT__TYPE, oldType, type));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NamedElement getVariable()
+  {
+    if (variable != null && variable.eIsProxy())
+    {
+      InternalEObject oldVariable = (InternalEObject)variable;
+      variable = (NamedElement)eResolveProxy(oldVariable);
+      if (variable != oldVariable)
+      {
+        if (eNotificationRequired())
+          eNotify(new ENotificationImpl(this, Notification.RESOLVE, SolverLanguagePackage.TYPED_ARGUMENT__VARIABLE, oldVariable, variable));
+      }
+    }
+    return variable;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NamedElement basicGetVariable()
+  {
+    return variable;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setVariable(NamedElement newVariable)
+  {
+    NamedElement oldVariable = variable;
+    variable = newVariable;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.TYPED_ARGUMENT__VARIABLE, oldVariable, variable));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.TYPED_ARGUMENT__TYPE:
+        if (resolve) return getType();
+        return basicGetType();
+      case SolverLanguagePackage.TYPED_ARGUMENT__VARIABLE:
+        if (resolve) return getVariable();
+        return basicGetVariable();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.TYPED_ARGUMENT__TYPE:
+        setType((NamedElement)newValue);
+        return;
+      case SolverLanguagePackage.TYPED_ARGUMENT__VARIABLE:
+        setVariable((NamedElement)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.TYPED_ARGUMENT__TYPE:
+        setType((NamedElement)null);
+        return;
+      case SolverLanguagePackage.TYPED_ARGUMENT__VARIABLE:
+        setVariable((NamedElement)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.TYPED_ARGUMENT__TYPE:
+        return type != null;
+      case SolverLanguagePackage.TYPED_ARGUMENT__VARIABLE:
+        return variable != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //TypedArgumentImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TypedStarArgumentImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TypedStarArgumentImpl.java
new file mode 100644
index 00000000..dd2b46bc
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/TypedStarArgumentImpl.java
@@ -0,0 +1,175 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.NamedElement;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+import org.eclipse.viatra.solver.language.solverLanguage.TypedStarArgument;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Typed Star Argument</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.TypedStarArgumentImpl#getType <em>Type</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class TypedStarArgumentImpl extends ArgumentImpl implements TypedStarArgument
+{
+  /**
+   * The cached value of the '{@link #getType() <em>Type</em>}' reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getType()
+   * @generated
+   * @ordered
+   */
+  protected NamedElement type;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected TypedStarArgumentImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.TYPED_STAR_ARGUMENT;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NamedElement getType()
+  {
+    if (type != null && type.eIsProxy())
+    {
+      InternalEObject oldType = (InternalEObject)type;
+      type = (NamedElement)eResolveProxy(oldType);
+      if (type != oldType)
+      {
+        if (eNotificationRequired())
+          eNotify(new ENotificationImpl(this, Notification.RESOLVE, SolverLanguagePackage.TYPED_STAR_ARGUMENT__TYPE, oldType, type));
+      }
+    }
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NamedElement basicGetType()
+  {
+    return type;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setType(NamedElement newType)
+  {
+    NamedElement oldType = type;
+    type = newType;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.TYPED_STAR_ARGUMENT__TYPE, oldType, type));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.TYPED_STAR_ARGUMENT__TYPE:
+        if (resolve) return getType();
+        return basicGetType();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.TYPED_STAR_ARGUMENT__TYPE:
+        setType((NamedElement)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.TYPED_STAR_ARGUMENT__TYPE:
+        setType((NamedElement)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.TYPED_STAR_ARGUMENT__TYPE:
+        return type != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //TypedStarArgumentImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnaryExpressionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnaryExpressionImpl.java
new file mode 100644
index 00000000..ee5ebfbb
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnaryExpressionImpl.java
@@ -0,0 +1,270 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+import org.eclipse.viatra.solver.language.solverLanguage.UnaryExpression;
+import org.eclipse.viatra.solver.language.solverLanguage.UnaryOp;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Unary Expression</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.UnaryExpressionImpl#getOp <em>Op</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.UnaryExpressionImpl#getBody <em>Body</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class UnaryExpressionImpl extends ExpressionImpl implements UnaryExpression
+{
+  /**
+   * The default value of the '{@link #getOp() <em>Op</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOp()
+   * @generated
+   * @ordered
+   */
+  protected static final UnaryOp OP_EDEFAULT = UnaryOp.NEG;
+  /**
+   * The cached value of the '{@link #getOp() <em>Op</em>}' attribute.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getOp()
+   * @generated
+   * @ordered
+   */
+  protected UnaryOp op = OP_EDEFAULT;
+  /**
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getBody()
+   * @generated
+   * @ordered
+   */
+  protected Expression body;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected UnaryExpressionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.UNARY_EXPRESSION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public UnaryOp getOp()
+  {
+    return op;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setOp(UnaryOp newOp)
+  {
+    UnaryOp oldOp = op;
+    op = newOp == null ? OP_EDEFAULT : newOp;
+    if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.UNARY_EXPRESSION__OP, oldOp, op));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getBody()
+  {
+    return body;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
+  {
+    Expression oldBody = body;
+    body = newBody;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.UNARY_EXPRESSION__BODY, oldBody, newBody);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setBody(Expression newBody)
+  {
+    if (newBody != body)
+    {
+      NotificationChain msgs = null;
+      if (body != null)
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.UNARY_EXPRESSION__BODY, null, msgs);
+      if (newBody != null)
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.UNARY_EXPRESSION__BODY, null, msgs);
+      msgs = basicSetBody(newBody, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.UNARY_EXPRESSION__BODY, newBody, newBody));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNARY_EXPRESSION__BODY:
+        return basicSetBody(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNARY_EXPRESSION__OP:
+        return getOp();
+      case SolverLanguagePackage.UNARY_EXPRESSION__BODY:
+        return getBody();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNARY_EXPRESSION__OP:
+        setOp((UnaryOp)newValue);
+        return;
+      case SolverLanguagePackage.UNARY_EXPRESSION__BODY:
+        setBody((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNARY_EXPRESSION__OP:
+        setOp(OP_EDEFAULT);
+        return;
+      case SolverLanguagePackage.UNARY_EXPRESSION__BODY:
+        setBody((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNARY_EXPRESSION__OP:
+        return op != OP_EDEFAULT;
+      case SolverLanguagePackage.UNARY_EXPRESSION__BODY:
+        return body != null;
+    }
+    return super.eIsSet(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public String toString()
+  {
+    if (eIsProxy()) return super.toString();
+    StringBuilder result = new StringBuilder(super.toString());
+    result.append(" (op: ");
+    result.append(op);
+    result.append(')');
+    return result.toString();
+  }
+} //UnaryExpressionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnnamedErrorPrediateDefinitionImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnnamedErrorPrediateDefinitionImpl.java
new file mode 100644
index 00000000..cd6a3271
--- /dev/null
+++ b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnnamedErrorPrediateDefinitionImpl.java
@@ -0,0 +1,270 @@
+/**
+ * generated by Xtext 2.21.0
+ */
+package org.eclipse.viatra.solver.language.solverLanguage.impl;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.viatra.solver.language.solverLanguage.ArgumentList;
+import org.eclipse.viatra.solver.language.solverLanguage.Expression;
+import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
+import org.eclipse.viatra.solver.language.solverLanguage.UnnamedErrorPrediateDefinition;
+/**
+ * <!-- begin-user-doc -->
+ * An implementation of the model object '<em><b>Unnamed Error Prediate Definition</b></em>'.
+ * <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.UnnamedErrorPrediateDefinitionImpl#getArgumentList <em>Argument List</em>}</li>
+ *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.UnnamedErrorPrediateDefinitionImpl#getBody <em>Body</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class UnnamedErrorPrediateDefinitionImpl extends StatementImpl implements UnnamedErrorPrediateDefinition
+{
+  /**
+   * The cached value of the '{@link #getArgumentList() <em>Argument List</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getArgumentList()
+   * @generated
+   * @ordered
+   */
+  protected ArgumentList argumentList;
+  /**
+   * The cached value of the '{@link #getBody() <em>Body</em>}' containment reference.
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @see #getBody()
+   * @generated
+   * @ordered
+   */
+  protected Expression body;
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  protected UnnamedErrorPrediateDefinitionImpl()
+  {
+    super();
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  protected EClass eStaticClass()
+  {
+    return SolverLanguagePackage.Literals.UNNAMED_ERROR_PREDIATE_DEFINITION;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public ArgumentList getArgumentList()
+  {
+    return argumentList;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetArgumentList(ArgumentList newArgumentList, NotificationChain msgs)
+  {
+    ArgumentList oldArgumentList = argumentList;
+    argumentList = newArgumentList;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST, oldArgumentList, newArgumentList);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setArgumentList(ArgumentList newArgumentList)
+  {
+    if (newArgumentList != argumentList)
+    {
+      NotificationChain msgs = null;
+      if (argumentList != null)
+        msgs = ((InternalEObject)argumentList).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST, null, msgs);
+      if (newArgumentList != null)
+        msgs = ((InternalEObject)newArgumentList).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST, null, msgs);
+      msgs = basicSetArgumentList(newArgumentList, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST, newArgumentList, newArgumentList));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Expression getBody()
+  {
+    return body;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  public NotificationChain basicSetBody(Expression newBody, NotificationChain msgs)
+  {
+    Expression oldBody = body;
+    body = newBody;
+    if (eNotificationRequired())
+    {
+      ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY, oldBody, newBody);
+      if (msgs == null) msgs = notification; else msgs.add(notification);
+    }
+    return msgs;
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void setBody(Expression newBody)
+  {
+    if (newBody != body)
+    {
+      NotificationChain msgs = null;
+      if (body != null)
+        msgs = ((InternalEObject)body).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY, null, msgs);
+      if (newBody != null)
+        msgs = ((InternalEObject)newBody).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY, null, msgs);
+      msgs = basicSetBody(newBody, msgs);
+      if (msgs != null) msgs.dispatch();
+    }
+    else if (eNotificationRequired())
+      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY, newBody, newBody));
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST:
+        return basicSetArgumentList(null, msgs);
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY:
+        return basicSetBody(null, msgs);
+    }
+    return super.eInverseRemove(otherEnd, featureID, msgs);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public Object eGet(int featureID, boolean resolve, boolean coreType)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST:
+        return getArgumentList();
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY:
+        return getBody();
+    }
+    return super.eGet(featureID, resolve, coreType);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eSet(int featureID, Object newValue)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST:
+        setArgumentList((ArgumentList)newValue);
+        return;
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY:
+        setBody((Expression)newValue);
+        return;
+    }
+    super.eSet(featureID, newValue);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public void eUnset(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST:
+        setArgumentList((ArgumentList)null);
+        return;
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY:
+        setBody((Expression)null);
+        return;
+    }
+    super.eUnset(featureID);
+  }
+  /**
+   * <!-- begin-user-doc -->
+   * <!-- end-user-doc -->
+   * @generated
+   */
+  @Override
+  public boolean eIsSet(int featureID)
+  {
+    switch (featureID)
+    {
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__ARGUMENT_LIST:
+        return argumentList != null;
+      case SolverLanguagePackage.UNNAMED_ERROR_PREDIATE_DEFINITION__BODY:
+        return body != null;
+    }
+    return super.eIsSet(featureID);
+  }
+} //UnnamedErrorPrediateDefinitionImpl
diff --git a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnnamedObjectImpl.java b/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnnamedObjectImpl.java
deleted file mode 100644
index 39bec164..00000000
--- a/Application/org.eclipse.viatra.solver.language/src-gen/org/eclipse/viatra/solver/language/solverLanguage/impl/UnnamedObjectImpl.java
+++ /dev/null
@@ -1,179 +0,0 @@
-/**
- * generated by Xtext 2.18.0.M3
- */
-package org.eclipse.viatra.solver.language.solverLanguage.impl;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.viatra.solver.language.solverLanguage.SolverLanguagePackage;
-import org.eclipse.viatra.solver.language.solverLanguage.UnnamedObject;
-/**
- * <!-- begin-user-doc -->
- * An implementation of the model object '<em><b>Unnamed Object</b></em>'.
- * <!-- end-user-doc -->
- * <p>
- * The following features are implemented:
- * </p>
- * <ul>
- *   <li>{@link org.eclipse.viatra.solver.language.solverLanguage.impl.UnnamedObjectImpl#getName <em>Name</em>}</li>
- * </ul>
- *
- * @generated
- */
-public class UnnamedObjectImpl extends ObjectImpl implements UnnamedObject
-{
-  /**
-   * The default value of the '{@link #getName() <em>Name</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getName()
-   * @generated
-   * @ordered
-   */
-  protected static final String NAME_EDEFAULT = null;
-  /**
-   * The cached value of the '{@link #getName() <em>Name</em>}' attribute.
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @see #getName()
-   * @generated
-   * @ordered
-   */
-  protected String name = NAME_EDEFAULT;
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  protected UnnamedObjectImpl()
-  {
-    super();
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  protected EClass eStaticClass()
-  {
-    return SolverLanguagePackage.Literals.UNNAMED_OBJECT;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public String getName()
-  {
-    return name;
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void setName(String newName)
-  {
-    String oldName = name;
-    name = newName;
-    if (eNotificationRequired())
-      eNotify(new ENotificationImpl(this, Notification.SET, SolverLanguagePackage.UNNAMED_OBJECT__NAME, oldName, name));
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public Object eGet(int featureID, boolean resolve, boolean coreType)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.UNNAMED_OBJECT__NAME:
-        return getName();
-    }
-    return super.eGet(featureID, resolve, coreType);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eSet(int featureID, Object newValue)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.UNNAMED_OBJECT__NAME:
-        setName((String)newValue);
-        return;
-    }
-    super.eSet(featureID, newValue);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public void eUnset(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.UNNAMED_OBJECT__NAME:
-        setName(NAME_EDEFAULT);
-        return;
-    }
-    super.eUnset(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public boolean eIsSet(int featureID)
-  {
-    switch (featureID)
-    {
-      case SolverLanguagePackage.UNNAMED_OBJECT__NAME:
-        return NAME_EDEFAULT == null ? name != null : !NAME_EDEFAULT.equals(name);
-    }
-    return super.eIsSet(featureID);
-  }
-  /**
-   * <!-- begin-user-doc -->
-   * <!-- end-user-doc -->
-   * @generated
-   */
-  @Override
-  public String toString()
-  {
-    if (eIsProxy()) return super.toString();
-    StringBuilder result = new StringBuilder(super.toString());
-    result.append(" (name: ");
-    result.append(name);
-    result.append(')');
-    return result.toString();
-  }
-} //UnnamedObjectImpl