3rdparty/boost/boost/concept/detail/general.hpp

   1 // Copyright David Abrahams 2006. Distributed under the Boost
   2 // Software License, Version 1.0. (See accompanying
   3 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   4 #ifndef BOOST_CONCEPT_DETAIL_GENERAL_DWA2006429_HPP
   5 # define BOOST_CONCEPT_DETAIL_GENERAL_DWA2006429_HPP
   6
   7 # include <boost/config.hpp>
   8 # include <boost/preprocessor/cat.hpp>
   9 # include <boost/concept/detail/backward_compatibility.hpp>
  10
  11 # ifdef BOOST_OLD_CONCEPT_SUPPORT
  12 #  include <boost/concept/detail/has_constraints.hpp>
  13 #  include <boost/type_traits/conditional.hpp>
  14 # endif
  15
  16 // This implementation works on Comeau and GCC, all the way back to
  17 // 2.95
  18 namespace boost { namespace concepts {
  19
  20 template <class ModelFn>
  21 struct requirement_;
  22
  23 namespace detail
  24 {
  25   template <void(*)()> struct instantiate {};
  26 }
  27
  28 template <class Model>
  29 struct requirement
  30 {
  31     static void failed() { ((Model*)0)->~Model(); }
  32 };
  33
  34 struct failed {};
  35
  36 template <class Model>
  37 struct requirement<failed ************ Model::************>
  38 {
  39     static void failed() { ((Model*)0)->~Model(); }
  40 };
  41
  42 # ifdef BOOST_OLD_CONCEPT_SUPPORT
  43
  44 template <class Model>
  45 struct constraint
  46 {
  47     static void failed() { ((Model*)0)->constraints(); }
  48 };
  49
  50 template <class Model>
  51 struct requirement_<void(*)(Model)>
  52   : boost::conditional<
  53         concepts::not_satisfied<Model>::value
  54       , constraint<Model>
  55       , requirement<failed ************ Model::************>
  56     >::type
  57 {};
  58
  59 # else
  60
  61 // For GCC-2.x, these can't have exactly the same name
  62 template <class Model>
  63 struct requirement_<void(*)(Model)>
  64     : requirement<failed ************ Model::************>
  65 {};
  66
  67 # endif
  68
  69 #  define BOOST_CONCEPT_ASSERT_FN( ModelFnPtr )             \
  70     typedef ::boost::concepts::detail::instantiate<          \
  71     &::boost::concepts::requirement_<ModelFnPtr>::failed>    \
  72       BOOST_PP_CAT(boost_concept_check,__LINE__)             \
  73       BOOST_ATTRIBUTE_UNUSED
  74
  75 }}
  76
  77 #endif // BOOST_CONCEPT_DETAIL_GENERAL_DWA2006429_HPP