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diff --git a/trunk/qpid/cpp/src/qpid/amqp_0_10/apply.h b/trunk/qpid/cpp/src/qpid/amqp_0_10/apply.h
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+#ifndef QPID_AMQP_0_10_APPLY_H
+#define QPID_AMQP_0_10_APPLY_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/optional.hpp>
+
+namespace qpid {
+namespace amqp_0_10 {
+
+template <class F, class R=typename F::result_type> struct FunctionAndResult {
+ F* functor;
+ boost::optional<R> result;
+
+ FunctionAndResult() : functor(0) {}
+ template <class T> void invoke(T& t) { result=(*functor)(t); }
+ template <class T> void invoke(const T& t) { result=(*functor)(t); }
+ R getResult() { return *result; }
+};
+
+// void result is special case.
+template <class F> struct FunctionAndResult<F, void> {
+ F* functor;
+
+ FunctionAndResult() : functor(0) {}
+ template <class T> void invoke(T& t) { (*functor)(t); }
+ void getResult() {}
+};
+
+// Metafunction returning correct abstract visitor for Visitable type.
+template <class Visitable> struct VisitorType {
+ typedef typename Visitable::Visitor type;
+};
+template <class Visitable> struct VisitorType<const Visitable> {
+ typedef typename Visitable::ConstVisitor type;
+};
+
+template <class Visitor, class F>
+struct ApplyVisitorBase : public Visitor, public FunctionAndResult<F> {};
+
+// Specialize for each visitor type
+template <class Visitable, class F> struct ApplyVisitor;
+
+/** Apply a functor to a visitable object.
+ * The functor can have operator() overloads for each visitable type
+ * and/or templated operator().
+ */
+template <class F, class Visitable>
+typename F::result_type apply(F& functor, Visitable& visitable) {
+ ApplyVisitor<typename VisitorType<Visitable>::type, F> visitor;
+ visitor.functor=&functor;
+ visitable.accept(visitor);
+ return visitor.getResult();
+}
+
+template <class F, class Visitable>
+typename F::result_type apply(const F& functor, Visitable& visitable) {
+ ApplyVisitor<typename VisitorType<Visitable>::type, const F> visitor;
+ visitor.functor=&functor;
+ visitable.accept(visitor);
+ return visitor.getResult();
+}
+
+template <class R> struct ApplyFunctor { typedef R result_type; };
+
+}} // namespace qpid::amqp_0_10
+
+#endif /*!QPID_AMQP_0_10_APPLY_H*/