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Macro BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION

BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION — A macro which expands to a metafunction which tests whether a member function with a particular name and signature exists.

Synopsis

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

BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION(trait, name)

Description

BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION is a macro which expands to a metafunction. The metafunction tests whether a member function with a particular name and signature exists. The macro takes the form of BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION(trait,name) where

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

BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION generates a metafunction called "trait" where 'trait' is the macro parameter.

template<class BOOST_TTI_TP_T,class BOOST_TTI_R,class BOOST_TTI_FS,class BOOST_TTI_TAG>
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'.
                     The enclosing type can be a class, struct, or union.
                              OR
                     a pointer to member function as a single type.
  
  BOOST_TTI_TP_R   = (optional) the return type of the member function
            if the first parameter is the enclosing type.
  
  BOOST_TTI_TP_FS  = (optional) the parameters of the member function as a boost::mpl forward sequence
            if the first parameter is the enclosing type and the member function parameters
            are not empty.
  
  BOOST_TTI_TP_TAG = (optional) a boost::function_types tag to apply to the member function
            if the first parameter is the enclosing type and a tag is needed.
  
  returns = 'value' is true if the 'name' exists, 
            with the appropriate member function type,
            otherwise 'value' is false.


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