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Diffstat (limited to 'boost/tti/has_data.hpp')
-rw-r--r-- | boost/tti/has_data.hpp | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/boost/tti/has_data.hpp b/boost/tti/has_data.hpp new file mode 100644 index 0000000000..b967891e83 --- /dev/null +++ b/boost/tti/has_data.hpp @@ -0,0 +1,98 @@ + +// (C) Copyright Edward Diener 2012,2013 +// Use, modification and distribution are subject to 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). + +#if !defined(BOOST_TTI_HAS_DATA_HPP) +#define BOOST_TTI_HAS_DATA_HPP + +#include <boost/config.hpp> +#include <boost/preprocessor/cat.hpp> +#include <boost/type_traits/remove_const.hpp> +#include <boost/tti/gen/has_data_gen.hpp> +#include <boost/tti/detail/ddata.hpp> + +/* + + The succeeding comments in this file are in doxygen format. + +*/ + +/** \file +*/ + +/// Expands to a metafunction which tests whether member data or static member with a particular name and type exists. +/** + + trait = the name of the metafunction. + + name = the name of the inner member to introspect. + + generates a metafunction called "trait" where 'trait' is the macro parameter. + + template<class BOOST_TTI_TP_T,class BOOST_TTI_TP_TYPE> + struct trait + { + static const value = unspecified; + typedef mpl::bool_<true-or-false> type; + }; + + The metafunction types and return: + + BOOST_TTI_TP_T = the enclosing type in which to look for our 'name' + + BOOST_TTI_TP_TYPE = The type of the member data or static member. + + returns = 'value' is true if the 'name' exists, with the correct data type, + otherwise 'value' is false. + +*/ +#define BOOST_TTI_TRAIT_HAS_DATA(trait,name) \ + BOOST_TTI_DETAIL_TRAIT_HAS_DATA(trait,name) \ + template<class BOOST_TTI_TP_T,class BOOST_TTI_TP_TYPE> \ + struct trait \ + { \ + typedef typename \ + BOOST_PP_CAT(trait,_detail_hd) \ + < \ + typename boost::remove_const<BOOST_TTI_TP_T>::type, \ + BOOST_TTI_TP_TYPE \ + >::type type; \ + BOOST_STATIC_CONSTANT(bool,value=type::value); \ + }; \ +/**/ + +/// Expands to a metafunction which tests whether member data or static member data with a particular name and type exists. +/** + + name = the name of the inner member. + + generates a metafunction called "has_data_name" where 'name' is the macro parameter. + + template<class BOOST_TTI_TP_T,class BOOST_TTI_TP_TYPE> + struct has_data_name + { + static const value = unspecified; + typedef mpl::bool_<true-or-false> type; + }; + + The metafunction types and return: + + BOOST_TTI_TP_T = the enclosing type in which to look for our 'name' + + BOOST_TTI_TP_TYPE = The type of the member data or static member. + + returns = 'value' is true if the 'name' exists, with the correct data type, + otherwise 'value' is false. + +*/ +#define BOOST_TTI_HAS_DATA(name) \ + BOOST_TTI_TRAIT_HAS_DATA \ + ( \ + BOOST_TTI_HAS_DATA_GEN(name), \ + name \ + ) \ +/**/ + +#endif // BOOST_TTI_HAS_DATA_HPP |