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diff --git a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/persistent/ImmutableStack.java b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/persistent/ImmutableStack.java
new file mode 100644
index 000000000..825639159
--- /dev/null
+++ b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/persistent/ImmutableStack.java
@@ -0,0 +1,94 @@
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management
+ * in Industry THTH ry.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     VTT Technical Research Centre of Finland - initial API and implementation
+ *******************************************************************************/
+package org.simantics.utils.datastructures.persistent;
+
+public abstract class ImmutableStack<T> {
+	
+	private ImmutableStack() {		
+	}
+	
+	private static class SingleStackNode<T> extends ImmutableStack<T> {
+		ImmutableStack<T> parent;
+		T value;
+		
+		public SingleStackNode(ImmutableStack<T> parent, T value) {		
+			this.parent = parent;
+			this.value = value;
+		}
+
+		@Override
+		public T get(int i) {
+			return i==0 ? value : parent.get(i-1);
+		}	
+	}
+	
+	private static class MultiStackNode<T> extends ImmutableStack<T> {
+		ImmutableStack<T> parent;
+		T[] values;
+		
+		public MultiStackNode(ImmutableStack<T> parent, T[] values) {		
+			this.parent = parent;
+			this.values = values;
+		}
+
+		@Override
+		public T get(int i) {
+			return i<values.length ? values[i] : parent.get(i-values.length);
+		}	
+	}
+	
+	private static class EmptyStack<T> extends ImmutableStack<T> {
+
+		@Override
+		public T get(int i) {
+			throw new IllegalArgumentException("No such element in stack.");
+		}
+		
+	}
+	
+	@SuppressWarnings({ "rawtypes" })
+	static final EmptyStack EMPTY = new EmptyStack();
+	
+	public ImmutableStack<T> push(T value) {
+		return new SingleStackNode<T>(this, value);
+	}
+	
+	public ImmutableStack<T> push(T[] values) {
+		if(values.length > 1)
+			return new MultiStackNode<T>(this, values);
+		else if(values.length == 1)
+			return new SingleStackNode<T>(this, values[0]);
+		else
+			return this;
+	}
+	
+	public abstract T get(int i); 
+	
+	@SuppressWarnings("unchecked")
+	public static <T> ImmutableStack<T> empty() {
+		return (ImmutableStack<T>)EMPTY;
+	}
+	
+	public static <T> ImmutableStack<T> of(T value) {
+		return new SingleStackNode<T>(null, value);
+	}
+	
+	@SuppressWarnings("unchecked")
+	public static <T> ImmutableStack<T> of(T[] values) {
+		if(values.length > 1)
+			return new MultiStackNode<T>((ImmutableStack<T>)empty(), values);
+		else if(values.length == 1)
+			return new SingleStackNode<T>((ImmutableStack<T>)empty(), values[0]);
+		else
+			return empty();
+	}
+}