/*=============================================================================
    Copyright (c) 2006 Eric Niebler

    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_SEGMENTS_04052005_1141)
#define BOOST_FUSION_SEGMENTS_04052005_1141

#include <boost/fusion/support/config.hpp>
#include <boost/type_traits/is_const.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/fusion/sequence/intrinsic_fwd.hpp>
#include <boost/fusion/support/tag_of.hpp>

namespace boost {
namespace fusion {
// Special tags:
struct sequence_facade_tag;
struct iterator_range_tag;

// segments: returns a sequence of sequences
namespace extension {
template <typename Tag>
struct segments_impl
{
    template <typename Sequence>
    struct apply {};
};

template <>
struct segments_impl<sequence_facade_tag>
{
    template <typename Sequence>
    struct apply : Sequence::template segments<Sequence> {};
};

template <>
struct segments_impl<iterator_range_tag>;
}

namespace result_of {
template <typename Sequence>
struct segments
{
    typedef typename traits::tag_of<Sequence>::type tag_type;

    typedef typename
    extension::segments_impl<tag_type>::template apply<Sequence>::type
    type;
};
}

template <typename Sequence>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
inline typename
lazy_disable_if<
is_const<Sequence>
, result_of::segments<Sequence>
>::type
segments(Sequence& seq)
{
    typedef typename traits::tag_of<Sequence>::type tag_type;
    return extension::segments_impl<tag_type>::template apply<Sequence>::call(seq);
}

template <typename Sequence>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
inline typename result_of::segments<Sequence const>::type
segments(Sequence const& seq)
{
    typedef typename traits::tag_of<Sequence const>::type tag_type;
    return extension::segments_impl<tag_type>::template apply<Sequence const>::call(seq);
}
}
}

#endif
