ecency-mobile/ios/Pods/boost-for-react-native/boost/fusion/sequence/intrinsic/begin.hpp

99 lines
2.9 KiB
C++

/*=============================================================================
Copyright (c) 2001-2011 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_BEGIN_04052005_1132)
#define FUSION_BEGIN_04052005_1132
#include <boost/fusion/support/config.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/mpl/empty_base.hpp>
#include <boost/mpl/if.hpp>
#include <boost/fusion/sequence/intrinsic_fwd.hpp>
#include <boost/fusion/support/tag_of.hpp>
#include <boost/fusion/support/is_sequence.hpp>
#include <boost/fusion/support/is_segmented.hpp>
#include <boost/fusion/sequence/intrinsic/detail/segmented_begin.hpp>
namespace boost { namespace fusion
{
// Special tags:
struct sequence_facade_tag; // iterator facade tag
struct boost_tuple_tag; // boost::tuples::tuple tag
struct boost_array_tag; // boost::array tag
struct mpl_sequence_tag; // mpl sequence tag
struct std_pair_tag; // std::pair tag
namespace extension
{
template <typename Tag>
struct begin_impl
{
template <typename Sequence>
struct apply
: mpl::if_<
traits::is_segmented<Sequence>
, detail::segmented_begin<Sequence>
, mpl::empty_base
>::type
{};
};
template <>
struct begin_impl<sequence_facade_tag>
{
template <typename Sequence>
struct apply : Sequence::template begin<Sequence> {};
};
template <>
struct begin_impl<boost_tuple_tag>;
template <>
struct begin_impl<boost_array_tag>;
template <>
struct begin_impl<mpl_sequence_tag>;
template <>
struct begin_impl<std_pair_tag>;
}
namespace result_of
{
template <typename Sequence>
struct begin
: extension::begin_impl<typename detail::tag_of<Sequence>::type>::
template apply<Sequence>
{};
}
template <typename Sequence>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
inline typename
lazy_enable_if<
traits::is_sequence<Sequence>
, result_of::begin<Sequence>
>::type const
begin(Sequence& seq)
{
return result_of::begin<Sequence>::call(seq);
}
template <typename Sequence>
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
inline typename
lazy_enable_if<
traits::is_sequence<Sequence>
, result_of::begin<Sequence const>
>::type const
begin(Sequence const& seq)
{
return result_of::begin<Sequence const>::call(seq);
}
}}
#endif