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diff --git a/qpid/cpp/src/qpid/framing/Visitor.h b/qpid/cpp/src/qpid/framing/Visitor.h
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+#ifndef QPID_FRAMING_VISITOR_H
+#define QPID_FRAMING_VISITOR_H
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+#include <boost/mpl/vector.hpp>
+#include <boost/type_traits/remove_reference.hpp>
+#include <boost/preprocessor/seq/for_each.hpp>
+
+namespace qpid {
+namespace framing {
+
+/** @file Generic visitor pattern. */
+
+/** visit() interface for type T (optional return type R, default void.)
+ * To create  a visitor for a set of types T1, T2 ... do this:
+ * struct MyVisitor : public Visit<T1>, public Visit<T2> ... {};
+ *@param T Type to visit, must be forward declared, need not be defined.
+ */
+template <class T, class R=void> struct Visit {
+    typedef R ReturnType;
+    typedef T VisitType;
+    
+    virtual ~Visit() {}
+    virtual R visit(T&) = 0;
+};
+
+
+#define QPID_VISITOR_DECL(_1,_2,T) class T;
+
+#define QPID_VISITOR_BASE(_1,_2,T) , public ::qpid::framing::Visit<T>
+
+/** Convenience macro to generate a visitor interface.
+ * QPID_VISITOR(MyVisitor,(A)(B)(C)); is equivalent to:
+ * @code
+ * class A; class B; class C;
+ * class MyVisitor : public Visit<A> , public Visit<B> , public Visit<C> {};
+ * @endcode
+ * @param visitor name of the generated visitor class.
+ * @param bases a sequence of visitable types in the form (T1)(T2)...
+ * The odd parenthesized notation is due to quirks of the preprocesser.
+ */
+#define QPID_VISITOR(visitor,types) \
+    BOOST_PP_SEQ_FOR_EACH(QPID_VISITOR_DECL, _, types) \
+    class visitor : public ::qpid::framing::Visit<BOOST_PP_SEQ_HEAD(types)> \
+    BOOST_PP_SEQ_FOR_EACH(QPID_VISITOR_BASE, _, BOOST_PP_SEQ_TAIL(types)) \
+    {}
+
+/** Root class for hierarchy of objects visitable by Visitor V.
+ * Defines virtual accept()
+ */
+template <class V, class R=void>
+struct VisitableRoot {
+    typedef V VisitorType;
+    typedef R ReturnType;
+    virtual ~VisitableRoot() {}
+    virtual R accept(V& v) = 0;
+};
+
+/** Base class for concrete visitable classes, implements accept().
+ * @param T type of visitable class (CRTP)
+ * @param Base base class to inherit from.
+ */
+template <class T, class Base>
+struct Visitable : public Base {
+    void accept(typename Base::VisitorType& v) {
+        static_cast<Visit<T>& >(v).visit(static_cast<T&>(*this));
+    }
+};
+
+}} // namespace qpid::framing
+
+#endif  /*!QPID_FRAMING_VISITOR_H*/