Bill Somerville 4ebe6417a5 Squashed 'boost/' content from commit b4feb19f2
git-subtree-dir: boost
git-subtree-split: b4feb19f287ee92d87a9624b5d36b7cf46aeadeb
2018-06-09 21:48:32 +01:00

48 lines
1.6 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_PUSH_FRONT_07162005_0749)
#define FUSION_PUSH_FRONT_07162005_0749
#include <boost/fusion/support/config.hpp>
#include <boost/fusion/support/detail/as_fusion_element.hpp>
#include <boost/fusion/view/joint_view/joint_view.hpp>
#include <boost/fusion/view/single_view/single_view.hpp>
#include <boost/fusion/support/is_sequence.hpp>
#include <boost/utility/enable_if.hpp>
namespace boost { namespace fusion
{
namespace result_of
{
template <typename Sequence, typename T>
struct push_front
{
typedef fusion::single_view<typename detail::as_fusion_element<T>::type> single_view;
typedef joint_view<single_view const, Sequence> type;
};
}
template <typename Sequence, typename T>
BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
inline typename
lazy_enable_if<
traits::is_sequence<Sequence>
, result_of::push_front<Sequence const, T>
>::type
push_front(Sequence const& seq, T const& x)
{
typedef typename result_of::push_front<Sequence const, T> push_front;
typedef typename push_front::single_view single_view;
typedef typename push_front::type result;
single_view x_(x);
return result(x_, seq);
}
}}
#endif