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diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/util/Sets.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/util/Sets.java
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+/*******************************************************************************
+ * Copyright (c) 2010-2019, Gabor Bergmann, IncQuery Labs Ltd.
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *   Gabor Bergmann - initial API and implementation
+ *******************************************************************************/
+package tools.refinery.viatra.runtime.matchers.util;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+/**
+ * This class was motivated by the similar Sets class from Guava to provide simple set manipulation
+ * functionality. However, as starting with version 2.3 the runtime of VIATRA Query should not depend on Guava, 
+ * not even internally, the relevant subset of Sets methods will be reimplemented here.
+ * 
+ * <p> The current approach is to delegate to Eclipse Collections wherever possible.
+ * Such glue methods are useful so that downstream clients can avoid directly depending on Eclipse Collections.
+ * 
+ * <p> Without an equivalent from Eclipse Collections, {@link #cartesianProduct(List)} is implemented here from scratch.
+ *  
+ * @author Gabor Bergmann
+ * @since 2.3
+ */
+public final class Sets {
+    
+    /**
+     * @since 2.4
+     */
+    public static <A> Set<A> newSet(Iterable<A> elements) {
+        return org.eclipse.collections.impl.factory.Sets.mutable.ofAll(elements);
+    }
+
+    public static <A> Set<A> intersection(Set<A> left, Set<A> right) {
+        return org.eclipse.collections.impl.factory.Sets.intersect(left, right);
+    }
+
+    public static <A> Set<A> difference(Set<A> left, Set<A> right) {
+        return org.eclipse.collections.impl.factory.Sets.difference(left, right);
+    }
+
+    public static <A> Set<A> union(Set<A> left, Set<A> right) {
+        return org.eclipse.collections.impl.factory.Sets.union(left, right);
+    }
+    
+    public static <A> Set<? extends Set<A>> powerSet(Set<A> set) {
+        return org.eclipse.collections.impl.factory.Sets.powerSet(set);
+    }
+
+    public static <A> Set<List<A>> cartesianProduct(List<? extends Set<? extends A>> setsList) {
+        
+        class Suffix { // simple immutable linked list
+            private A head;
+            private Suffix next;
+
+            public Suffix(A head, Suffix next) {
+                super();
+                this.head = head;
+                this.next = next;
+            }
+
+            public List<A> toList() {
+                ArrayList<A> result = new ArrayList<>();
+                for (Suffix cursor = this; cursor!=null; cursor = cursor.next)
+                    result.add(cursor.head);
+                return result;
+            }
+        }
+        
+        // build result lists from end to start, in the form of suffixes 
+        Stream<Suffix> suffixes = Stream.of((Suffix) null /* empty suffix*/); 
+        for (int i = setsList.size()-1; i>=0; --i) { // iterate sets in reverse order
+            Set<? extends A> set = setsList.get(i);
+            suffixes = suffixes.flatMap(suffix -> set.stream().map(newElement -> new Suffix(newElement, suffix)));
+        }
+        
+        
+        return suffixes.map(Suffix::toList).collect(Collectors.toSet());
+    }
+    
+    
+}