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/preprocessor/cat.hpp>

     8 

     9 # ifdef BOOST_OLD_CONCEPT_SUPPORT

    10 #  include <boost/concept/detail/has_constraints.hpp>

    11 #  include <boost/mpl/if.hpp>

    12 # endif

    13 

    14 // This implementation works on Comeau and GCC, all the way back to

    15 // 2.95

    16 namespace boost { namespace concept {

    17 

    18 template <class ModelFn>

    19 struct requirement_;

    20 

    21 namespace detail

    22 {

    23   template <void(*)()> struct instantiate {};

    24 }

    25 

    26 template <class Model>

    27 struct requirement

    28 {

    29     static void failed() { ((Model*)0)->~Model(); }

    30 };

    31 

    32 # ifdef BOOST_OLD_CONCEPT_SUPPORT

    33 

    34 template <class Model>

    35 struct constraint

    36 {

    37     static void failed() { ((Model*)0)->constraints(); }

    38 };

    39   

    40 template <class Model>

    41 struct requirement_<void(*)(Model)>

    42   : mpl::if_<

    43         concept::not_satisfied<Model>

    44       , constraint<Model>

    45       , requirement<Model>

    46     >::type

    47 {};

    48   

    49 # else

    50 

    51 // For GCC-2.x, these can't have exactly the same name

    52 template <class Model>

    53 struct requirement_<void(*)(Model)>

    54   : requirement<Model>

    55 {};

    56   

    57 # endif

    58 

    59 #  define BOOST_CONCEPT_ASSERT_FN( ModelFnPtr )             \

    60     typedef ::boost::concept::detail::instantiate<          \

    61     &::boost::concept::requirement_<ModelFnPtr>::failed>    \

    62       BOOST_PP_CAT(boost_concept_check,__LINE__)

    63 

    64 }}

    65 

    66 #endif // BOOST_CONCEPT_DETAIL_GENERAL_DWA2006429_HPP