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## Macro BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION_TEMPLATE

BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION_TEMPLATE — A macro which expands to a metafunction which tests whether an inner member function template with a particular name exists.

## Synopsis

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

    BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION_TEMPLATE(trait, name, ...)

## Description

BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION_TEMPLATE is a macro which expands to a metafunction. The metafunction tests whether an inner member function template with a particular name exists. The macro takes the form of BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION_TEMPLATE(trait,name,...) where

trait = the name of the metafunction
name = inner member function template name
... = variadic parameters.

The variadic parameter(s) are either:

A sequence of valid instantiations for the member function template parameters ie. 'int,long,double' etc.

or

A single variadic parameter which is a Boost PP array whose elements are a sequence of valid instantiations for the member function template parameters ie. '(3,(int,long,double))' etc. This form is allowed in order to be compatible with using the non-variadic form of this macro.

BOOST_TTI_TRAIT_HAS_MEMBER_FUNCTION_TEMPLATE generates a metafunction called "trait" where 'trait' is the first 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
                         which encapsulates a single instantiation of
                         the member function template.

      BOOST_TTI_TP_R   = (optional) the return type of the member function template
                in a single instantiation of the member function template
                if the first parameter is the enclosing type.

      BOOST_TTI_TP_FS  = (optional) the parameters of the member function template as a boost::mpl forward sequence
                if the first parameter is the enclosing type and the member function template parameters
                are not empty. These parameters are a single instantiation of the member function template.

      BOOST_TTI_TP_TAG = (optional) a boost::function_types tag to apply to the member function template
                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 template type,
                otherwise 'value' is false.