ceph/src/boost/boost/fusion/view/transform_view/detail/deref_impl.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3     Copyright (c) 2018 Kohei Takahashi
   4
   5     Distributed under the Boost Software License, Version 1.0. (See accompanying
   6     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   7 ==============================================================================*/
   8 #if !defined(FUSION_DEREF_IMPL_07162005_1026)
   9 #define FUSION_DEREF_IMPL_07162005_1026
  10
  11 #include <boost/fusion/support/config.hpp>
  12 #include <boost/fusion/iterator/deref.hpp>
  13 #include <boost/utility/result_of.hpp>
  14
  15 namespace boost { namespace fusion
  16 {
  17     struct transform_view_iterator_tag;
  18     struct transform_view_iterator2_tag;
  19
  20     namespace extension
  21     {
  22         template <typename Tag>
  23         struct deref_impl;
  24
  25         // Unary Version
  26         template <>
  27         struct deref_impl<transform_view_iterator_tag>
  28         {
  29             template <typename Iterator>
  30             struct apply
  31             {
  32                 typedef typename
  33                     result_of::deref<typename Iterator::first_type>::type
  34                 value_type;
  35
  36                 typedef typename Iterator::transform_type F;
  37                 typedef typename boost::result_of<F(value_type)>::type type;
  38
  39                 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  40                 static type
  41                 call(Iterator const& i)
  42                 {
  43                     return i.f(*i.first);
  44                 }
  45             };
  46         };
  47
  48         // Binary Version
  49         template <>
  50         struct deref_impl<transform_view_iterator2_tag>
  51         {
  52             template <typename Iterator>
  53             struct apply
  54             {
  55                 typedef typename
  56                     result_of::deref<typename Iterator::first1_type>::type
  57                 value1_type;
  58                 typedef typename
  59                     result_of::deref<typename Iterator::first2_type>::type
  60                 value2_type;
  61
  62                 typedef typename Iterator::transform_type F;
  63                 typedef typename boost::result_of<F(value1_type, value2_type)>::type type;
  64
  65                 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  66                 static type
  67                 call(Iterator const& i)
  68                 {
  69                     return i.f(*i.first1, *i.first2);
  70                 }
  71             };
  72         };
  73     }
  74 }}
  75
  76 #endif
  77
  78