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diff --git a/qpid/cpp/src/qpid/framing/variant.h b/qpid/cpp/src/qpid/framing/variant.h
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+++ b/qpid/cpp/src/qpid/framing/variant.h
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+#ifndef QPID_FRAMING_VARIANT_H
+#define QPID_FRAMING_VARIANT_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.
+ *
+ */
+
+/**@file Tools for using boost::variant. */
+
+
+#include <boost/variant.hpp>
+
+namespace qpid {
+namespace framing {
+class Buffer;
+
+/** boost::static_visitor that throws an exception if variant contains a blank.
+ * Subclasses need to have a using() declaration, which can be generated
+ * with QPID_USING_NOBLANK(R)
+ */
+template <class R=void>
+struct NoBlankVisitor : public boost::static_visitor<R> {
+    R foundBlank() const {
+        assert(0);
+        throw Exception(QPID_MSG("Invalid variant value."));
+    }
+    R operator()(const boost::blank&) const { return foundBlank(); }
+    R operator()(boost::blank&) const { return foundBlank(); }
+};
+
+
+}} // qpid::framing
+
+
+/** Generate a using statement, needed in visitors inheriting NoBlankVisitor
+ *  @param R return type.
+ */
+#define QPID_USING_NOBLANK(R) using ::qpid::framing::NoBlankVisitor<R>::operator()
+
+namespace qpid {
+namespace framing {
+
+/** Convert the variant value to type R. */
+template <class R> struct ConvertVisitor : public NoBlankVisitor<R> {
+    QPID_USING_NOBLANK(R);
+    template <class T> R operator()(T& t) const { return t; }
+};
+
+/** Convert the address of variant value to type R. */
+template <class R> struct AddressVisitor : public NoBlankVisitor<R> {
+    QPID_USING_NOBLANK(R);
+    template <class T> R operator()(T& t) const { return &t; }
+};
+
+/** Apply a visitor to the nested variant.*/
+template<class V>
+struct ApplyVisitor : public NoBlankVisitor<typename V::result_type> {
+    QPID_USING_NOBLANK(typename V::result_type);
+    const V& visitor;
+    ApplyVisitor(const V& v) : visitor(v) {}
+    template <class T> typename V::result_type operator()(T& t) const {
+        return boost::apply_visitor(visitor, t);
+    }
+};
+
+/** Convenience function to construct and apply an ApplyVisitor */
+template <class Visitor, class Visitable>
+typename Visitor::result_type applyApplyVisitor(const Visitor& visitor, Visitable& visitable) {
+    return boost::apply_visitor(ApplyVisitor<Visitor>(visitor), visitable);
+}
+
+}} // namespace qpid::framing
+
+    
+#endif  /*!QPID_FRAMING_VARIANT_H*/