Chris@16: // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
Chris@16: // (C) Copyright 2003-2007 Jonathan Turkanis
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
Chris@16: 
Chris@16: // See http://www.boost.org/libs/iostreams for documentation.
Chris@16: 
Chris@16: #ifndef BOOST_IOSTREAMS_DETAIL_BOOL_TRAIT_DEF_HPP_INCLUDED
Chris@16: #define BOOST_IOSTREAMS_DETAIL_BOOL_TRAIT_DEF_HPP_INCLUDED     
Chris@16: 
Chris@16: #include <boost/config.hpp> // BOOST_STATIC_CONSTANT.
Chris@16: #include <boost/iostreams/detail/template_params.hpp>
Chris@16: #include <boost/mpl/aux_/lambda_support.hpp>
Chris@16: #include <boost/mpl/bool.hpp>
Chris@16: #include <boost/preprocessor/cat.hpp>
Chris@16: #include <boost/preprocessor/repetition/enum_params.hpp>
Chris@16: #include <boost/type_traits/detail/yes_no_type.hpp>
Chris@16:  
Chris@16: // 
Chris@16: // Macro name: BOOST_IOSTREAMS_BOOL_TRAIT_DEF
Chris@16: // Description: Used to generate the traits classes is_istream, is_ostream,
Chris@16: //      etc.
Chris@16: //
Chris@16: #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x582))
Chris@16: # define BOOST_IOSTREAMS_TRAIT_NAMESPACE(trait)
Chris@16: #else
Chris@16: # define BOOST_IOSTREAMS_TRAIT_NAMESPACE(trait) BOOST_PP_CAT(trait, _impl_):: 
Chris@16: #endif
Chris@16: #define BOOST_IOSTREAMS_BOOL_TRAIT_DEF(trait, type, arity) \
Chris@16:     namespace BOOST_PP_CAT(trait, _impl_) { \
Chris@16:       BOOST_IOSTREAMS_TEMPLATE_PARAMS(arity, T) \
Chris@16:       type_traits::yes_type helper \
Chris@16:           (const volatile type BOOST_IOSTREAMS_TEMPLATE_ARGS(arity, T)*); \
Chris@16:       type_traits::no_type helper(...); \
Chris@16:       template<typename T> \
Chris@16:       struct impl { \
Chris@16:            BOOST_STATIC_CONSTANT(bool, value = \
Chris@16:            (sizeof(BOOST_IOSTREAMS_TRAIT_NAMESPACE(trait) \
Chris@16:               helper(static_cast<T*>(0))) == \
Chris@16:                 sizeof(type_traits::yes_type))); \
Chris@16:       }; \
Chris@16:     } \
Chris@16:     template<typename T> \
Chris@16:     struct trait \
Chris@16:         : mpl::bool_<BOOST_PP_CAT(trait, _impl_)::impl<T>::value> \
Chris@16:     { BOOST_MPL_AUX_LAMBDA_SUPPORT(1, trait, (T)) }; \
Chris@16:     /**/
Chris@16: 
Chris@16: #endif // #ifndef BOOST_IOSTREAMS_DETAIL_BOOL_TRAIT_DEF_HPP_INCLUDED