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BOOST_TTI_TRAIT_HAS_STATIC_MEMBER_DATA — A macro which expands to a metafunction which tests whether a static member data with a particular name and type exists.


// In header: <boost/tti/has_static_member_data.hpp>



BOOST_TTI_TRAIT_HAS_STATIC_MEMBER_DATA is a macro which expands to a metafunction. The metafunction tests whether static member data with a particular name and type exists. The macro takes the form of BOOST_TTI_TRAIT_HAS_STATIC_MEMBER_DATA(trait,name) where

trait = the name of the metafunction
name = the name of the inner member.

BOOST_TTI_TRAIT_HAS_STATIC_MEMBER_DATA 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.
                      The enclosing type can be a class, struct, or union.
                      If the type is a union, static member data can only
                      be found if the C++11 unrestricted union is implemented
                      by the compiler being used, since prior to C++11 a union
                      could not have static data members.
  BOOST_TTI_TP_TYPE = the type of the static member data.
  returns = 'value' is true if the 'name' exists,
            with the BOOST_TTI_TP_TYPE type,
            within the enclosing BOOST_TTI_TP_T type,
            otherwise 'value' is false.