boost_1_45_0/boost/fusion/view/nview/detail/begin_impl.hpp

/*=============================================================================
    Copyright (c) 2009 Hartmut Kaiser

    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(BOOST_FUSION_NVIEW_BEGIN_IMPL_SEP_23_2009_1036PM)
#define BOOST_FUSION_NVIEW_BEGIN_IMPL_SEP_23_2009_1036PM

#include <boost/mpl/begin.hpp>
#include <boost/fusion/sequence/intrinsic/begin.hpp>

namespace boost { namespace fusion
{
    struct nview_tag;

    template <typename Sequence, typename Pos>
    struct nview_iterator;

    namespace extension
    {
        template<typename Tag>
        struct begin_impl;

        template<>
        struct begin_impl<nview_tag>
        {
            template<typename Sequence>
            struct apply
            {
                typedef typename Sequence::index_type index_type;

                typedef nview_iterator<Sequence, 
                    typename mpl::begin<index_type>::type> type;

                static type call(Sequence& s)
                {
                    return type(s);
                }
            };
        };
    }

}}

#endif