has_data.hpp File Reference

#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>

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Macros
#define	BOOST_TTI_TRAIT_HAS_DATA(trait, name)
	Expands to a metafunction which tests whether member data or static member with a particular name and type exists. More...
#define	BOOST_TTI_HAS_DATA(name)
	Expands to a metafunction which tests whether member data or static member data with a particular name and type exists. More...

Macro Definition Documentation

#define BOOST_TTI_HAS_DATA

(

name

)

Value:

BOOST_TTI_TRAIT_HAS_DATA \
  ( \
  BOOST_TTI_HAS_DATA_GEN(name), \
  name \
  ) \

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_TRAIT_HAS_DATA	(		trait,
			name
	)

Value:

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 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.