ceph/src/boost/libs/fusion/include/boost/fusion/algorithm/transformation/push_front.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3
   4     Distributed under the Boost Software License, Version 1.0. (See accompanying
   5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 ==============================================================================*/
   7 #if !defined(FUSION_PUSH_FRONT_07162005_0749)
   8 #define FUSION_PUSH_FRONT_07162005_0749
   9
  10 #include <boost/fusion/support/config.hpp>
  11 #include <boost/fusion/support/detail/as_fusion_element.hpp>
  12 #include <boost/fusion/view/joint_view/joint_view.hpp>
  13 #include <boost/fusion/view/single_view/single_view.hpp>
  14 #include <boost/fusion/support/is_sequence.hpp>
  15 #include <boost/utility/enable_if.hpp>
  16
  17 namespace boost { namespace fusion
  18 {
  19     namespace result_of
  20     {
  21         template <typename Sequence, typename T>
  22         struct push_front
  23         {
  24             typedef fusion::single_view<typename detail::as_fusion_element<T>::type> single_view;
  25             typedef joint_view<single_view const, Sequence> type;
  26         };
  27     }
  28
  29     template <typename Sequence, typename T>
  30     BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  31     inline typename
  32         lazy_enable_if<
  33             traits::is_sequence<Sequence>
  34           , result_of::push_front<Sequence const, T>
  35         >::type
  36     push_front(Sequence const& seq, T const& x)
  37     {
  38         typedef typename result_of::push_front<Sequence const, T> push_front;
  39         typedef typename push_front::single_view single_view;
  40         typedef typename push_front::type result;
  41         single_view x_(x);
  42         return result(x_, seq);
  43     }
  44 }}
  45
  46 #endif
  47