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diff --git a/indra/llcommon/lleventemitter.h b/indra/llcommon/lleventemitter.h
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+++ b/indra/llcommon/lleventemitter.h
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+/** 
+ * @file lleventemitter.h
+ * @brief General event emitter class
+ *
+ * Copyright (c) 2005-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+// header guard
+#ifndef LL_EVENTEMITTER_H
+#define LL_EVENTEMITTER_H
+
+// standard headers
+#include <algorithm>
+#include <typeinfo>
+#include <iostream>
+#include <string>
+#include <list>
+
+#include "stdtypes.h"
+
+///////////////////////////////////////////////////////////////////////////////
+//	templatized emitter class
+template < class T >
+class eventEmitter
+{
+	public:
+		typedef typename T::EventType EventType;
+		typedef std::list< T* > ObserverContainer;
+		typedef void ( T::*observerMethod )( const EventType& );
+
+	protected:
+		ObserverContainer observers;
+
+	public:
+		eventEmitter () { };
+
+		~eventEmitter () { };
+
+		///////////////////////////////////////////////////////////////////////////////
+		//
+		BOOL addObserver ( T* observerIn )
+		{
+			if ( ! observerIn )
+				return FALSE;
+
+			// check if observer already exists
+			if ( std::find ( observers.begin (), observers.end (), observerIn ) != observers.end () )
+				return FALSE;
+
+			// save it
+			observers.push_back ( observerIn );
+
+			return true;
+		};
+
+		///////////////////////////////////////////////////////////////////////////////
+		//
+		BOOL remObserver ( T* observerIn )
+		{
+			if ( ! observerIn )
+				return FALSE;
+
+			observers.remove ( observerIn );
+
+			return TRUE;
+		};
+
+		///////////////////////////////////////////////////////////////////////////////
+		//
+		void update ( observerMethod method, const EventType& msgIn )
+		{
+			typename std::list< T* >::iterator iter = observers.begin ();
+
+			while ( iter != observers.end () )
+			{
+				( ( *iter )->*method ) ( msgIn );
+
+				++iter;
+			};
+		};
+};
+
+#endif // lleventemitter_h