1 files changed, 37 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/util/ISetMemory.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/util/ISetMemory.java
new file mode 100644
index 00000000..0c03da48
--- /dev/null
+++ b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/util/ISetMemory.java
@@ -0,0 +1,37 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2018, Gabor Bergmann, IncQueryLabs 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
+ *******************************************************************************/
+package tools.refinery.viatra.runtime.matchers.util;
+
+import java.util.function.BiConsumer;
+
+/**
+ * An {@link IMemory} that always contains values with a 0 or +1 multiplicity.
+ * 
+ * <p> In case a write operation causes underflow or overflow, an {@link IllegalStateException} is thrown.
+ * 
+ * @author Gabor Bergmann
+ * @since 2.0
+ */
+public interface ISetMemory<T> extends IMemory<T> {
+    
+    @Override
+    default void forEachEntryWithMultiplicities(BiConsumer<T, Integer> entryConsumer) {
+        for (T t : this.distinctValues()) entryConsumer.accept(t, 1);
+    }
+    
+
+    @Override
+    default boolean removeOne(T value) {
+        if (!removeOneOrNop(value))
+            throw new IllegalStateException();
+        return true;
+    }
+
+
+}