[ceph.git] / ceph / src / boost / libs / concept_check / include / boost / concept_check / has_constraints.hpp

// Copyright David Abrahams 2006. Distributed under 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)
#ifndef BOOST_CONCEPT_CHECK_HAS_CONSTRAINTS_DWA2006429_HPP
# define BOOST_CONCEPT_CHECK_HAS_CONSTRAINTS_DWA2006429_HPP

namespace boost { namespace concept_checking { 

// Here we implement the "metafunction" that detects whether a
// constraints metafunction exists
typedef char yes;
typedef char (&no)[2];

template <class Model, void (Model::*)()>
struct wrap_constraints {};
    
template <class Model>
inline yes has_constraints_(Model*, wrap_constraints<Model,&Model::constraints>* = 0);
inline no has_constraints_(...);

template <class Model>
struct has_constraints
{
    BOOST_STATIC_CONSTANT(
        bool
      , value = sizeof( concept_checking::has_constraints_((Model*)0) ) == 1 );
};

}} // namespace boost::concept_checking

#endif // BOOST_CONCEPT_CHECK_HAS_CONSTRAINTS_DWA2006429_HPP
Commit	Line	Data
7c673cae FG	1	// Copyright David Abrahams 2006. Distributed under the Boost
	2	// Software License, Version 1.0. (See accompanying
	3	// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
	4	#ifndef BOOST_CONCEPT_CHECK_HAS_CONSTRAINTS_DWA2006429_HPP
	5	# define BOOST_CONCEPT_CHECK_HAS_CONSTRAINTS_DWA2006429_HPP
	6
	7	namespace boost { namespace concept_checking {
	8
	9	// Here we implement the "metafunction" that detects whether a
	10	// constraints metafunction exists
	11	typedef char yes;
	12	typedef char (&no)[2];
	13
	14	template <class Model, void (Model::*)()>
	15	struct wrap_constraints {};
	16
	17	template <class Model>
	18	inline yes has_constraints_(Model, wrap_constraints<Model,&Model::constraints> = 0);
	19	inline no has_constraints_(...);
	20
	21	template <class Model>
	22	struct has_constraints
	23	{
	24	BOOST_STATIC_CONSTANT(
	25	bool
	26	, value = sizeof( concept_checking::has_constraints_((Model*)0) ) == 1 );
	27	};
	28
	29	}} // namespace boost::concept_checking
	30
	31	#endif // BOOST_CONCEPT_CHECK_HAS_CONSTRAINTS_DWA2006429_HPP