// 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