ceph/src/boost/libs/phoenix/include/boost/phoenix/scope/scoped_environment.hpp

   1 /*==============================================================================
   2     Copyright (c) 2005-2010 Joel de Guzman
   3     Copyright (c) 2010 Thomas Heller
   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 #ifndef BOOST_PHOENIX_SCOPE_SCOPED_ENVIRONMENT_HPP
   9 #define BOOST_PHOENIX_SCOPE_SCOPED_ENVIRONMENT_HPP
  10
  11 #include <boost/phoenix/core/limits.hpp>
  12 #include <boost/mpl/int.hpp>
  13 #include <boost/fusion/sequence/sequence_facade.hpp>
  14 #include <boost/fusion/sequence/intrinsic/begin.hpp>
  15 #include <boost/fusion/sequence/intrinsic/end.hpp>
  16 #include <boost/fusion/sequence/intrinsic/size.hpp>
  17 #include <boost/fusion/sequence/intrinsic/value_at.hpp>
  18 #include <boost/fusion/sequence/intrinsic/at.hpp>
  19 #include <boost/fusion/support/category_of.hpp>
  20 #include <boost/fusion/include/pop_front.hpp>
  21 #include <boost/utility/result_of.hpp>
  22
  23 namespace boost { namespace phoenix
  24 {
  25     template<typename Env, typename OuterEnv, typename Locals, typename Map>
  26     struct scoped_environment
  27         : fusion::sequence_facade<
  28             scoped_environment<Env, OuterEnv, Locals, Map>
  29           , fusion::random_access_traversal_tag
  30         >
  31     {
  32         typedef Env env_type;
  33         typedef OuterEnv outer_env_type;
  34         typedef Locals locals_type;
  35         typedef Map map_type;
  36
  37         scoped_environment(
  38             Env const & env_
  39           , OuterEnv const &outer_env_
  40           , Locals const &locals_
  41         )
  42             : env(env_)
  43             , outer_env(outer_env_)
  44             , locals(locals_)
  45         {}
  46
  47         scoped_environment(scoped_environment const & o)
  48             : env(o.env)
  49             , outer_env(o.outer_env)
  50             , locals(o.locals)
  51         {}
  52
  53         Env      const & env;
  54         OuterEnv const & outer_env;
  55         Locals   const & locals;
  56
  57         typedef typename
  58             fusion::result_of::pop_front<
  59                 typename add_const<
  60                     typename proto::detail::uncvref<Env>::type
  61                 >::type
  62             >::type
  63             args_type;
  64
  65         args_type args() const
  66         {
  67             return fusion::pop_front(env);
  68         }
  69
  70         #define BOOST_PHOENIX_ADAPT_SCOPED_ENVIRONMENT(INTRINSIC)               \
  71         template <typename Seq>                                                 \
  72         struct INTRINSIC                                                        \
  73         {                                                                       \
  74             typedef                                                             \
  75                 typename fusion::result_of::INTRINSIC<                          \
  76                     typename mpl::eval_if_c<                                    \
  77                         is_const<                                               \
  78                             typename remove_reference<                          \
  79                                 typename Seq::env_type                          \
  80                             >::type                                             \
  81                         >::value                                                \
  82                       , add_const<                                              \
  83                             typename proto::detail::uncvref<                    \
  84                                 typename Seq::env_type                          \
  85                             >::type                                             \
  86                         >                                                       \
  87                       , proto::detail::uncvref<                                 \
  88                             typename Seq::env_type                              \
  89                         >                                                       \
  90                     >::type                                                     \
  91                 >::type                                                         \
  92                 type;                                                           \
  93                                                                                 \
  94             static type call(Seq & seq)                                         \
  95             {                                                                   \
  96                 return fusion::INTRINSIC(seq.env);                              \
  97             }                                                                   \
  98         }                                                                       \
  99         /**/
 100         BOOST_PHOENIX_ADAPT_SCOPED_ENVIRONMENT(begin);
 101         BOOST_PHOENIX_ADAPT_SCOPED_ENVIRONMENT(end);
 102         BOOST_PHOENIX_ADAPT_SCOPED_ENVIRONMENT(size);
 103         #undef BOOST_PHOENIX_ADAPT_SCOPED_ENVIRONMENT
 104
 105         template <typename Seq, typename N>
 106         struct value_at
 107         {
 108             typedef
 109                 typename fusion::result_of::value_at<
 110                     typename mpl::eval_if_c<
 111                         is_const<
 112                             typename remove_reference<
 113                                 typename Seq::env_type
 114                             >::type
 115                         >::value
 116                       , add_const<
 117                             typename proto::detail::uncvref<
 118                                 typename Seq::env_type
 119                             >::type
 120                         >
 121                       , proto::detail::uncvref<
 122                             typename Seq::env_type
 123                         >
 124                     >::type
 125                   , N
 126                 >::type
 127                 type;
 128         };
 129
 130         template <typename Seq, typename N>
 131         struct at
 132         {
 133             typedef
 134                 typename fusion::result_of::at<
 135                     typename mpl::eval_if_c<
 136                         is_const<
 137                             typename remove_reference<
 138                                 typename Seq::env_type
 139                             >::type
 140                         >::value
 141                       , add_const<
 142                             typename proto::detail::uncvref<
 143                                 typename Seq::env_type
 144                             >::type
 145                         >
 146                       , proto::detail::uncvref<
 147                             typename Seq::env_type
 148                         >
 149                     >::type
 150                   , N
 151                 >::type
 152                 type;
 153
 154             static type call(Seq & seq)
 155             {
 156                 return fusion::at<N>(seq.env);
 157             }
 158         };
 159     };
 160
 161     template <typename Env, typename Dummy = void>
 162     struct is_scoped_environment : mpl::false_ {};
 163
 164     template <typename Env>
 165     struct is_scoped_environment<Env&> : is_scoped_environment<Env> {};
 166
 167     template <typename Env, typename OuterEnv, typename Locals, typename Map>
 168     struct is_scoped_environment<scoped_environment<Env, OuterEnv, Locals, Map> >
 169         : mpl::true_
 170     {};
 171
 172     template <typename Env, typename OuterEnv, typename Locals, typename Map>
 173     struct is_scoped_environment<scoped_environment<Env, OuterEnv, Locals, Map> const>
 174         : mpl::true_
 175     {};
 176 }}
 177
 178 #endif