vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/tti/has_member_data.hpp

107 lines
3.7 KiB
C++

// (C) Copyright Edward Diener 2011,2012,2013
// 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_MEMBER_DATA_HPP)
#define BOOST_TTI_HAS_MEMBER_DATA_HPP
#include <boost/config.hpp>
#include <boost/preprocessor/cat.hpp>
#include <boost/tti/detail/ddeftype.hpp>
#include <boost/tti/detail/dmem_data.hpp>
#include <boost/tti/gen/has_member_data_gen.hpp>
/*
The succeeding comments in this file are in doxygen format.
*/
/** \file
*/
/// Expands to a metafunction which tests whether a member data 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_ET,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_ET = the enclosing type in which to look for our 'name'
OR
The type of the member data in the form of a pointer
to member data.
BOOST_TTI_TP_TYPE = (optional) The type of the member data if the first
parameter is the enclosing type.
returns = 'value' is true if the 'name' exists, with the correct data type,
otherwise 'value' is false.
*/
#define BOOST_TTI_TRAIT_HAS_MEMBER_DATA(trait,name) \
BOOST_TTI_DETAIL_TRAIT_HAS_MEMBER_DATA(trait,name) \
template<class BOOST_TTI_TP_ET,class BOOST_TTI_TP_TYPE = BOOST_TTI_NAMESPACE::detail::deftype> \
struct trait \
{ \
typedef typename \
BOOST_PP_CAT(trait,_detail_hmd) \
< \
BOOST_TTI_TP_ET, \
BOOST_TTI_TP_TYPE \
>::type type; \
BOOST_STATIC_CONSTANT(bool,value=type::value); \
}; \
/**/
/// Expands to a metafunction which tests whether a member data with a particular name and type exists.
/**
name = the name of the inner member.
generates a metafunction called "has_member_data_name" where 'name' is the macro parameter.
template<class BOOST_TTI_TP_ET,class BOOST_TTI_TP_TYPE>
struct has_member_data_name
{
static const value = unspecified;
typedef mpl::bool_<true-or-false> type;
};
The metafunction types and return:
BOOST_TTI_TP_ET = the enclosing type in which to look for our 'name'
OR
The type of the member data in the form of a pointer
to member data.
BOOST_TTI_TP_TYPE = (optional) The type of the member data if the first
parameter is the enclosing type.
returns = 'value' is true if the 'name' exists, with the correct data type,
otherwise 'value' is false.
*/
#define BOOST_TTI_HAS_MEMBER_DATA(name) \
BOOST_TTI_TRAIT_HAS_MEMBER_DATA \
( \
BOOST_TTI_HAS_MEMBER_DATA_GEN(name), \
name \
) \
/**/
#endif // BOOST_TTI_HAS_MEMBER_DATA_HPP