--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/project/com.nokia.carbide.cpp.epoc.engine/src/com/nokia/carbide/internal/cpp/epoc/engine/model/TranslationUnitListener.java	Fri Apr 03 23:33:03 2009 +0100
@@ -0,0 +1,40 @@
+/*
+* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of the License "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description: 
+*
+*/
+package com.nokia.carbide.internal.cpp.epoc.engine.model;
+
+import com.nokia.carbide.internal.api.cpp.epoc.engine.dom.IASTNode;
+import com.nokia.carbide.internal.api.cpp.epoc.engine.dom.ITranslationUnitListener;
+import com.nokia.cpp.internal.api.utils.core.*;
+
+/**
+ * Listen to unauthorized external changes to the TU
+ */
+class TranslationUnitListener implements ITranslationUnitListener {
+	private boolean changesAllowed;
+	public void allowChanges(boolean allowed) {
+		Check.checkState(allowed != changesAllowed);
+		changesAllowed = allowed;
+	}
+	/* (non-Javadoc)
+	 * @see com.nokia.carbide.internal.api.cpp.epoc.engine.dom.ITranslationUnitListener#changedNode(com.nokia.carbide.internal.api.cpp.epoc.engine.dom.IASTNode)
+	 */
+	public void changedNode(IASTNode node) {
+		if (!changesAllowed)
+			throw new IllegalStateException("illegal change to translation unit outside model or view"); //$NON-NLS-1$
+	}
+	
+}
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