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

28 lines
912 B
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_EXCAHNGE_HPP
#define SPROUT_UTILITY_EXCAHNGE_HPP
#include <sprout/config.hpp>
#include <sprout/utility/forward.hpp>
#include <sprout/utility/move.hpp>
namespace sprout {
//
// 20.2.3 exchange
//
template<typename T, typename U = T>
inline SPROUT_CXX14_CONSTEXPR T
exchange(T& obj, U&& new_val) {
T old_val = sprout::move(obj);
obj = SPROUT_FORWARD(U, new_val);
return old_val;
}
} // namespace sprout
#endif // #ifndef SPROUT_UTILITY_EXCAHNGE_HPP