/*=============================================================================

    Copyright (c) 2001-2006 Joel de Guzman



    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)

==============================================================================*/

#if !defined(FUSION_DISTANCE_IMPL_09172005_0751)

#define FUSION_DISTANCE_IMPL_09172005_0751



#include <boost/mpl/minus.hpp>



namespace boost { namespace fusion

{

    struct vector_iterator_tag;



    namespace extension

    {

        template <typename Tag>

        struct distance_impl;



        template <>

        struct distance_impl<vector_iterator_tag>

        {

            template <typename First, typename Last>

            struct apply : mpl::minus<typename Last::index, typename First::index>

            {    

                static typename mpl::minus<

                    typename Last::index, typename First::index>::type

                call(First const&, Last const&)

                {

                    typedef typename mpl::minus<

                        typename Last::index, typename First::index>::type 

                    result;

                    return result();

                }

            };

        };

    }

}}



#endif

