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/*=============================================================================
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_ERASE_07232005_0534)
#define FUSION_ERASE_07232005_0534
#include <boost/fusion/support/config.hpp>
#include <boost/fusion/iterator/equal_to.hpp>
#include <boost/fusion/iterator/mpl/convert_iterator.hpp>
#include <boost/fusion/view/joint_view/joint_view.hpp>
#include <boost/fusion/view/iterator_range/iterator_range.hpp>
#include <boost/fusion/support/detail/as_fusion_element.hpp>
#include <boost/fusion/sequence/intrinsic/begin.hpp>
#include <boost/fusion/sequence/intrinsic/end.hpp>
#include <boost/fusion/adapted/mpl/mpl_iterator.hpp>
#include <boost/fusion/support/is_sequence.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/mpl/if.hpp>
namespace boost { namespace fusion
{
namespace result_of
{
template <typename Sequence, typename First>
struct compute_erase_last // put this in detail!!!
{
typedef typename result_of::end<Sequence>::type seq_last_type;
typedef typename convert_iterator<First>::type first_type;
typedef typename
mpl::if_<
result_of::equal_to<first_type, seq_last_type>
, first_type
, typename result_of::next<first_type>::type
>::type
type;
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
static type
call(First const& first, mpl::false_)
{
return fusion::next(convert_iterator<First>::call(first));
}
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
static type
call(First const& first, mpl::true_)
{
return convert_iterator<First>::call(first);
}
BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
static type
call(First const& first)
{
return call(first, result_of::equal_to<first_type, seq_last_type>());
}
};
struct use_default;
template <class T, class Default>
struct fusion_default_help
: mpl::if_<
is_same<T, use_default>
, Default
, T
>
{
};
template <
typename Sequence
, typename First
, typename Last = use_default>
struct erase
{
typedef typename result_of::begin<Sequence>::type seq_first_type;
typedef typename result_of::end<Sequence>::type seq_last_type;
BOOST_STATIC_ASSERT((!result_of::equal_to<seq_first_type, seq_last_type>::value));
typedef First FirstType;
typedef typename
fusion_default_help<
Last
, typename compute_erase_last<Sequence, First>::type
>::type
LastType;
typedef typename convert_iterator<FirstType>::type first_type;
typedef typename convert_iterator<LastType>::type last_type;
typedef iterator_range<seq_first_type, first_type> left_type;
typedef iterator_range<last_type, seq_last_type> right_type;
typedef joint_view<left_type, right_type> type;
};
}
template <typename Sequence, typename First>
BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
inline typename
lazy_enable_if<
traits::is_sequence<Sequence>
, typename result_of::erase<Sequence const, First>
>::type
erase(Sequence const& seq, First const& first)
{
typedef result_of::erase<Sequence const, First> result_of;
typedef typename result_of::left_type left_type;
typedef typename result_of::right_type right_type;
typedef typename result_of::type result_type;
left_type left(
fusion::begin(seq)
, convert_iterator<First>::call(first));
right_type right(
fusion::result_of::compute_erase_last<Sequence const, First>::call(first)
, fusion::end(seq));
return result_type(left, right);
}
template <typename Sequence, typename First, typename Last>
BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
inline typename result_of::erase<Sequence const, First, Last>::type
erase(Sequence const& seq, First const& first, Last const& last)
{
typedef result_of::erase<Sequence const, First, Last> result_of;
typedef typename result_of::left_type left_type;
typedef typename result_of::right_type right_type;
typedef typename result_of::type result_type;
left_type left(fusion::begin(seq), first);
right_type right(last, fusion::end(seq));
return result_type(left, right);
}
}}
#endif