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

    Copyright (c) 2003 Joel de Guzman

    Copyright (c) 2004 Peder Holt



    Use, modification and distribution is subject to 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_ITERATOR_PRIOR_HPP)

#define FUSION_ITERATOR_PRIOR_HPP



#include <boost/spirit/fusion/detail/config.hpp>

#include <boost/spirit/fusion/iterator/as_fusion_iterator.hpp>



namespace boost { namespace fusion

{

    namespace meta

    {

        template <typename Tag>

        struct prior_impl

        {

            template <typename Iterator>

            struct apply {};

        };



        template <typename Iterator>

        struct prior

        {

            typedef as_fusion_iterator<Iterator> converter;

            typedef typename converter::type iter;



            typedef typename

                prior_impl<FUSION_GET_TAG(iter)>::

                    template apply<iter>::type

            type;

        };

    }



    template <typename Iterator>

    inline typename meta::prior<Iterator>::type

    prior(Iterator const& i)

    {

        typedef as_fusion_iterator<Iterator> converter;

        typedef typename converter::type iter;



        return meta::prior_impl<FUSION_GET_TAG(iter)>::

            template apply<iter>::call(converter::convert(i));

    }

}}



#endif

