Sprout/sprout/utility/forward.hpp
2016-02-25 18:48:28 +09:00

57 lines
1.8 KiB
C++

/*=============================================================================
Copyright (c) 2011-2016 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
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 SPROUT_UTILITY_FORWARD_HPP
#define SPROUT_UTILITY_FORWARD_HPP
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/preprocessor/config.hpp>
#include <sprout/preprocessor/cat.hpp>
#include <sprout/preprocessor/variadic/size.hpp>
namespace sprout {
//
// forward
//
template<typename T>
inline SPROUT_CONSTEXPR T&&
forward(typename std::remove_reference<T>::type& t) SPROUT_NOEXCEPT {
return static_cast<T&&>(t);
}
template<typename T>
inline SPROUT_CONSTEXPR T&&
forward(typename std::remove_reference<T>::type&&) SPROUT_NOEXCEPT SPROUT_DELETED_FUNCTION_DECL
} // namespace sprout
#if defined(__INTEL_COMPILER) || defined(__ICL) || defined(__ICC) || defined(__ECC)
# define SPROUT_FORWARD_2(TYPE, VAR) \
static_cast<decltype(::sprout::forward<TYPE>(VAR))>(VAR)
#else
# define SPROUT_FORWARD_2(TYPE, VAR) \
::sprout::forward<TYPE>(VAR)
#endif
//
// SPROUT_AUTO_FORWARD
//
#define SPROUT_AUTO_FORWARD(VAR) SPROUT_FORWARD_2(decltype(VAR), VAR)
//
// SPROUT_FORWARD
//
#if SPROUT_PP_VARIADICS && !defined(_MSC_VER)
# define SPROUT_FORWARD_1(VAR) \
SPROUT_AUTO_FORWARD(VAR)
# define SPROUT_FORWARD(...) \
SPROUT_PP_CAT(SPROUT_FORWARD_, SPROUT_PP_VARIADIC_SIZE(__VA_ARGS__))(__VA_ARGS__)
#else
# define SPROUT_FORWARD(TYPE, VAR) \
SPROUT_FORWARD_2(TYPE, VAR)
#endif
#endif // #ifndef SPROUT_UTILITY_FORWARD_HPP