

#ifndef BOOST_MPL_AUX_ORDER_IMPL_HPP_INCLUDED

#define BOOST_MPL_AUX_ORDER_IMPL_HPP_INCLUDED



// Copyright Aleksey Gurtovoy 2003-2004

// Copyright David Abrahams 2003-2004

//

// 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)

//

// See http://www.boost.org/libs/mpl for documentation.



// $Source$

// $Date: 2004-10-13 14:25:11 -0400 (Wed, 13 Oct 2004) $

// $Revision: 25712 $



#include <boost/mpl/order_fwd.hpp>

#include <boost/mpl/if.hpp>

#include <boost/mpl/long.hpp>

#include <boost/mpl/has_key.hpp>

#include <boost/mpl/aux_/overload_names.hpp>

#include <boost/mpl/aux_/static_cast.hpp>

#include <boost/mpl/aux_/type_wrapper.hpp>

#include <boost/mpl/aux_/traits_lambda_spec.hpp>

#include <boost/mpl/aux_/config/msvc.hpp>

#include <boost/mpl/aux_/config/static_constant.hpp>

#include <boost/mpl/aux_/config/workaround.hpp>



namespace boost { namespace mpl {



// default implementation; requires 'Seq' to provide corresponding overloads 

// of BOOST_MPL_AUX_OVERLOAD_ORDER_BY_KEY



template< typename Seq, typename Key > struct x_order_impl

#if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1400)) \

    || BOOST_WORKAROUND(__EDG_VERSION__, <= 245)

{

    BOOST_STATIC_CONSTANT(long, value = 

          sizeof( BOOST_MPL_AUX_OVERLOAD_CALL_ORDER_BY_KEY(

              Seq

            , BOOST_MPL_AUX_STATIC_CAST(aux::type_wrapper<Key>*, 0)

            ) )

        );



    typedef long_<value> type;



#else // ISO98 C++

    : long_< 

          sizeof( BOOST_MPL_AUX_OVERLOAD_CALL_ORDER_BY_KEY(

              Seq

            , BOOST_MPL_AUX_STATIC_CAST(aux::type_wrapper<Key>*, 0)

            ) )

        >

{

#endif

};



template< typename Tag >

struct order_impl

{

    template< typename Seq, typename Key > struct apply

        : if_<

              typename has_key_impl<Tag>::template apply<Seq,Key>

            , x_order_impl<Seq,Key>

            , void_

            >::type

    {

    };

};



BOOST_MPL_ALGORITM_TRAITS_LAMBDA_SPEC(2,order_impl)



}}



#endif // BOOST_MPL_AUX_ORDER_IMPL_HPP_INCLUDED

