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diff --git a/src/js/util/mxUndoableEdit.js b/src/js/util/mxUndoableEdit.js
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+/**
+ * $Id: mxUndoableEdit.js,v 1.14 2010-09-15 16:58:51 gaudenz Exp $
+ * Copyright (c) 2006-2010, JGraph Ltd
+ */
+/**
+ * Class: mxUndoableEdit
+ * 
+ * Implements a composite undoable edit.
+ * 
+ * Constructor: mxUndoableEdit
+ * 
+ * Constructs a new undoable edit for the given source.
+ */
+function mxUndoableEdit(source, significant)
+{
+	this.source = source;
+	this.changes = [];
+	this.significant = (significant != null) ? significant : true;
+};
+
+/**
+ * Variable: source
+ * 
+ * Specifies the source of the edit.
+ */
+mxUndoableEdit.prototype.source = null;
+
+/**
+ * Variable: changes
+ * 
+ * Array that contains the changes that make up this edit. The changes are
+ * expected to either have an undo and redo function, or an execute
+ * function. Default is an empty array.
+ */
+mxUndoableEdit.prototype.changes = null;
+
+/**
+ * Variable: significant
+ * 
+ * Specifies if the undoable change is significant.
+ * Default is true.
+ */
+mxUndoableEdit.prototype.significant = null;
+
+/**
+ * Variable: undone
+ * 
+ * Specifies if this edit has been undone. Default is false.
+ */
+mxUndoableEdit.prototype.undone = false;
+
+/**
+ * Variable: redone
+ * 
+ * Specifies if this edit has been redone. Default is false.
+ */
+mxUndoableEdit.prototype.redone = false;
+
+/**
+ * Function: isEmpty
+ * 
+ * Returns true if the this edit contains no changes.
+ */
+mxUndoableEdit.prototype.isEmpty = function()
+{
+	return this.changes.length == 0;
+};
+
+/**
+ * Function: isSignificant
+ * 
+ * Returns <significant>.
+ */
+mxUndoableEdit.prototype.isSignificant = function()
+{
+	return this.significant;
+};
+
+/**
+ * Function: add
+ * 
+ * Adds the specified change to this edit. The change is an object that is
+ * expected to either have an undo and redo, or an execute function.
+ */
+mxUndoableEdit.prototype.add = function(change)
+{
+	this.changes.push(change);
+};
+
+/**
+ * Function: notify
+ * 
+ * Hook to notify any listeners of the changes after an <undo> or <redo>
+ * has been carried out. This implementation is empty.
+ */
+mxUndoableEdit.prototype.notify = function() { };
+
+/**
+ * Function: die
+ * 
+ * Hook to free resources after the edit has been removed from the command
+ * history. This implementation is empty.
+ */
+mxUndoableEdit.prototype.die = function() { };
+
+/**
+ * Function: undo
+ * 
+ * Undoes all changes in this edit.
+ */
+mxUndoableEdit.prototype.undo = function()
+{
+	if (!this.undone)
+	{
+		var count = this.changes.length;
+		
+		for (var i = count - 1; i >= 0; i--)
+		{
+			var change = this.changes[i];
+			
+			if (change.execute != null)
+			{
+				change.execute();
+			}
+			else if (change.undo != null)
+			{
+				change.undo();
+			}
+		}
+		
+		this.undone = true;
+		this.redone = false;
+	}
+	
+	this.notify();
+};
+
+/**
+ * Function: redo
+ * 
+ * Redoes all changes in this edit.
+ */
+mxUndoableEdit.prototype.redo = function()
+{
+	if (!this.redone)
+	{
+		var count = this.changes.length;
+		
+		for (var i = 0; i < count; i++)
+		{
+			var change = this.changes[i];
+			
+			if (change.execute != null)
+			{
+				change.execute();
+			}
+			else if (change.redo != null)
+			{
+				change.redo();
+			}
+		}
+		
+		this.undone = false;
+		this.redone = true;
+	}
+	
+	this.notify();
+};