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+#ifndef QPID_FRAMING_TEMPLATEVISITOR_H
+#define QPID_FRAMING_TEMPLATEVISITOR_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/fold.hpp>
+#include <boost/utility/value_init.hpp>
+
+namespace qpid {
+namespace framing {
+
+/**
+ * Metafunction to generate a visitor class derived from Base with a
+ * visit for each type in TypeList calling functor F. TypeList may be
+ * any boost::mpl type collection e.g. mpl::list.
+ *
+ * Generated class is: TemplateVisitor<Base, F, TypeList>::type
+ *
+ * @see make_visitor
+ */
+template <class VisitTemplate, class TypeList, class F>
+class TemplateVisitor
+{
+ struct Base : public VisitorBase {
+ F action;
+ Base(F f) : action(f) {}
+ using VisitorBase::visit;
+ };
+
+ template <class B, class T> struct Visit : public B {
+ Visit(F action) : B(action) {}
+ using B::visit;
+ void visit(const T& body) { action(body); }
+ };
+
+ typedef typename boost::mpl::fold<
+ TypeList, Base, Visit<boost::mpl::placeholders::_1,
+ boost::mpl::placeholders::_2>
+ >::type type;
+};
+
+/**
+ * Construct a TemplateVisitor to perform the given action,
+ * for example:
+ * @code
+ */
+template <class VisitorBase, class TypeList, class F>
+TemplateVisitor<VisitorBase,TypeList,F>::type make_visitor(F action) {
+ return TemplateVisitor<VisitorBase,TypeList,F>::type(action);
+};
+
+/**
+ * For method body classes in TypeList, invoke the corresponding function
+ * on Target and return true. For other body types return false.
+ */
+template <class TypeList, class Target>
+bool invoke(const AMQBody& body, Target& target) {
+ typename InvokeVisitor<TypeList, Target>::type v(target);
+ body.accept(v);
+ return v.target;
+}
+
+}} // namespace qpid::framing
+
+
+#endif /*!QPID_FRAMING_INVOKEVISITOR_H*/
+
+}} // namespace qpid::framing
+
+
+
+#endif /*!QPID_FRAMING_TEMPLATEVISITOR_H*/