hof/detail/using.hpp

0001 /*=============================================================================
0002     Copyright (c) 2016 Paul Fultz II
0003     using.hpp
0004     Distributed under the Boost Software License, Version 1.0. (See accompanying
0005     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 ==============================================================================*/
0007
0008 #ifndef BOOST_HOF_GUARD_USING_HPP
0009 #define BOOST_HOF_GUARD_USING_HPP
0010
0011 #include <boost/hof/config.hpp>
0012
0013 #if BOOST_HOF_HAS_TEMPLATE_ALIAS
0014 #define BOOST_HOF_USING(name, ...) using name = __VA_ARGS__
0015 #define BOOST_HOF_USING_TYPENAME(name, ...) using name = typename __VA_ARGS__
0016 #else
0017 #define BOOST_HOF_USING(name, ...) struct name : std::enable_if<true, __VA_ARGS__>::type {}
0018 #define BOOST_HOF_USING_TYPENAME(name, ...) struct name : __VA_ARGS__ {}
0019 #endif
0020
0021 #endif