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diff --git a/boost/bimap/tags/support/value_type_of.hpp b/boost/bimap/tags/support/value_type_of.hpp
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+++ b/boost/bimap/tags/support/value_type_of.hpp
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+// Boost.Bimap
+//
+// Copyright (c) 2006-2007 Matias Capeletto
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+/// \file tags/support/value_type_of.hpp
+/// \brief Consistent way to access the value type of a tagged or untagged type.
+
+#ifndef BOOST_BIMAP_TAGS_SUPPORT_VALUE_TYPE_OF_HPP
+#define BOOST_BIMAP_TAGS_SUPPORT_VALUE_TYPE_OF_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER>=1200)
+#pragma once
+#endif
+
+#include <boost/config.hpp>
+
+#include <boost/bimap/tags/tagged.hpp>
+
+/** \struct boost::bimaps::tags::support::value_type_of
+\brief Metafunction to work with tagged and untagged type uniformly
+
+\code
+template< class Type >
+struct value_type_of
+{
+    typedef {UntaggedType} type;
+};
+\endcode
+
+If the type is tagged this metafunction returns Type::value_type, and if it is not
+tagged it return the same type. This allows to work consistenly with tagged and
+untagged types.
+
+See also tagged, tag_of.
+                                                                                **/
+
+#ifndef BOOST_BIMAP_DOXYGEN_WILL_NOT_PROCESS_THE_FOLLOWING_LINES
+
+
+namespace boost {
+namespace bimaps {
+namespace tags {
+namespace support {
+
+
+// value_type_of metafunction
+
+template< class Type >
+struct value_type_of
+{
+    typedef Type type;
+};
+
+template< class Type, class Tag >
+struct value_type_of< tagged< Type, Tag > >
+{
+    typedef Type type;
+};
+
+
+} // namespace support
+} // namespace tags
+} // namespace bimaps
+} // namespace boost
+
+#endif // BOOST_BIMAP_DOXYGEN_WILL_NOT_PROCESS_THE_FOLLOWING_LINES
+
+#endif // BOOST_BIMAP_TAGS_SUPPORT_VALUE_TYPE_OF_HPP
+
+