| // Copyright David Abrahams 2005. Distributed under the Boost |
| // Software License, Version 1.0. (See accompanying |
| // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| #ifndef BOOST_DETAIL_IS_XXX_DWA20051011_HPP |
| # define BOOST_DETAIL_IS_XXX_DWA20051011_HPP |
| |
| # include <boost/config.hpp> |
| # include <boost/mpl/bool.hpp> |
| # include <boost/preprocessor/enum_params.hpp> |
| |
| # if defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) |
| # include <boost/type_traits/is_reference.hpp> |
| # include <boost/type_traits/add_reference.hpp> |
| |
| # define BOOST_DETAIL_IS_XXX_DEF(name, qualified_name, nargs) \ |
| template <class X_> \ |
| struct is_##name \ |
| { \ |
| typedef char yes; \ |
| typedef char (&no)[2]; \ |
| \ |
| static typename add_reference<X_>::type dummy; \ |
| \ |
| struct helpers \ |
| { \ |
| template < BOOST_PP_ENUM_PARAMS_Z(1, nargs, class U) > \ |
| static yes test( \ |
| qualified_name< BOOST_PP_ENUM_PARAMS_Z(1, nargs, U) >&, int \ |
| ); \ |
| \ |
| template <class U> \ |
| static no test(U&, ...); \ |
| }; \ |
| \ |
| BOOST_STATIC_CONSTANT( \ |
| bool, value \ |
| = !is_reference<X_>::value \ |
| & (sizeof(helpers::test(dummy, 0)) == sizeof(yes))); \ |
| \ |
| typedef mpl::bool_<value> type; \ |
| }; |
| |
| # else |
| |
| # define BOOST_DETAIL_IS_XXX_DEF(name, qualified_name, nargs) \ |
| template <class T> \ |
| struct is_##name : mpl::false_ \ |
| { \ |
| }; \ |
| \ |
| template < BOOST_PP_ENUM_PARAMS_Z(1, nargs, class T) > \ |
| struct is_##name< \ |
| qualified_name< BOOST_PP_ENUM_PARAMS_Z(1, nargs, T) > \ |
| > \ |
| : mpl::true_ \ |
| { \ |
| }; |
| |
| # endif |
| |
| #endif // BOOST_DETAIL_IS_XXX_DWA20051011_HPP |