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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

/// \file tags/support/apply_to_value_type.hpp
/// \brief Similar to mpl::apply but for tagged types.


#if defined(_MSC_VER) && (_MSC_VER>=1200)
#pragma once

#include <boost/config.hpp>

#include <boost/bimap/tags/tagged.hpp>
#include <boost/mpl/apply.hpp>

/** \struct boost::bimaps::tags::support::apply_to_value_type
\brief Higger order metafunction similar to mpl::apply but for tagged types.

template< class Metafunction, class TaggedType >
struct apply_to_value_type
    typedef tagged
        Metafuntion< value_type_of< TaggedType >::type >::type,
        tag_of< TaggedType >::type

    > type;

This higher order metafunctions is very useful, and it can be used with lambda

See also tagged.


namespace boost {
namespace bimaps {
namespace tags {
namespace support {

template < class F, class TaggedType >
struct apply_to_value_type;

template < class F, class ValueType, class Tag >
struct apply_to_value_type<F, tagged<ValueType,Tag> >
    typedef BOOST_DEDUCED_TYPENAME mpl::apply< F, ValueType >::type new_value_type;
    typedef tagged< new_value_type, Tag > type;

} // namespace support
} // namespace tags
} // namespace bimaps
} // namespace boost