boost/tti/has_function.hpp
// (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_FUNCTION_HPP)
#define BOOST_TTI_HAS_FUNCTION_HPP
#include <boost/config.hpp>
#include <boost/function_types/property_tags.hpp>
#include <boost/mpl/vector.hpp>
#include <boost/preprocessor/cat.hpp>
#include <boost/tti/detail/dfunction.hpp>
#include <boost/tti/gen/has_function_gen.hpp>
/*
The succeeding comments in this file are in doxygen format.
*/
/** \file
*/
/// A macro which expands to a metafunction which tests whether a member function or a static member function with a particular name and signature exists.
/**
BOOST_TTI_TRAIT_HAS_FUNCTION is a macro which expands to a metafunction.
The metafunction tests whether a member function or a static member function with a particular name
and signature exists. The macro takes the form of BOOST_TTI_TRAIT_HAS_FUNCTION(trait,name) where
trait = the name of the metafunction <br/>
name = the name of the inner member.
BOOST_TTI_TRAIT_HAS_FUNCTION generates a metafunction called "trait" where 'trait' is the macro parameter.
@code
template<class BOOST_TTI_TP_T,class BOOST_TTI_TP_R,class BOOST_TTI_TP_FS,class BOOST_TTI_TP_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.
BOOST_TTI_TP_R = the return type of the function
BOOST_TTI_TP_FS = (optional) the parameters of the function as a boost::mpl forward sequence
if function parameters are not empty.
BOOST_TTI_TP_TAG = (optional) a boost::function_types tag to apply to the function
if the need for a tag exists.
returns = 'value' is true if the 'name' exists,
with the appropriate static member function type,
otherwise 'value' is false.
@endcode
*/
#define BOOST_TTI_TRAIT_HAS_FUNCTION(trait,name) \
BOOST_TTI_DETAIL_TRAIT_HAS_FUNCTION(trait,name) \
template<class BOOST_TTI_TP_T,class BOOST_TTI_TP_R,class BOOST_TTI_TP_FS = boost::mpl::vector<>,class BOOST_TTI_TP_TAG = boost::function_types::null_tag> \
struct trait \
{ \
typedef typename \
BOOST_PP_CAT(trait,_detail_hf)<BOOST_TTI_TP_T,BOOST_TTI_TP_R,BOOST_TTI_TP_FS,BOOST_TTI_TP_TAG>::type type; \
BOOST_STATIC_CONSTANT(bool,value=type::value); \
}; \
/**/
/// A macro which expands to a metafunction which tests whether a member function or a static member function with a particular name and signature exists.
/**
BOOST_TTI_HAS_FUNCTION is a macro which expands to a metafunction.
The metafunction tests whether a member function or a static member function with a particular name
and signature exists. The macro takes the form of BOOST_TTI_HAS_FUNCTION(name) where
name = the name of the inner member.
BOOST_TTI_HAS_FUNCTION generates a metafunction called "has_function_name" where 'name' is the macro parameter.
@code
template<class BOOST_TTI_TP_T,class BOOST_TTI_TP_R,class BOOST_TTI_TP_FS,class BOOST_TTI_TP_TAG>
struct has_function_'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'.
The enclosing type can be a class, struct, or union.
BOOST_TTI_TP_R = the return type of the function
BOOST_TTI_TP_FS = (optional) the parameters of the function as a boost::mpl forward sequence
if function parameters are not empty.
BOOST_TTI_TP_TAG = (optional) a boost::function_types tag to apply to the function
if the need for a tag exists.
returns = 'value' is true if the 'name' exists,
with the appropriate function type,
otherwise 'value' is false.
@endcode
*/
#define BOOST_TTI_HAS_FUNCTION(name) \
BOOST_TTI_TRAIT_HAS_FUNCTION \
( \
BOOST_TTI_HAS_FUNCTION_GEN(name), \
name \
) \
/**/
#endif // BOOST_TTI_HAS_FUNCTION_HPP