Sprout/sprout/functional/multiplies.hpp
2017-07-29 14:20:01 +09:00

49 lines
1.4 KiB
C++

/*=============================================================================
Copyright (c) 2011 RiSK (sscrisk)
https://github.com/sscrisk/CEL---ConstExpr-Library
Copyright (c) 2011-2017 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_FUNCTIONAL_MULTIPLIES_HPP
#define SPROUT_FUNCTIONAL_MULTIPLIES_HPP
#include <utility>
#include <sprout/config.hpp>
#include <sprout/utility/forward.hpp>
#include <sprout/functional/transparent.hpp>
namespace sprout {
// 20.8.4 Arithmetic operations
template<typename T = void>
struct multiplies {
public:
typedef T first_argument_type;
typedef T second_argument_type;
typedef T result_type;
public:
SPROUT_CONSTEXPR T operator()(T const& x, T const& y) const {
return x * y;
}
};
template<>
struct multiplies<void>
: public sprout::transparent<>
{
public:
template<typename T, typename U>
SPROUT_CONSTEXPR decltype(std::declval<T>() * std::declval<U>())
operator()(T&& x, U&& y)
const SPROUT_NOEXCEPT_IF_EXPR(std::declval<T>() * std::declval<U>())
{
return SPROUT_FORWARD(T, x) * SPROUT_FORWARD(U, y);
}
};
} // namespace sprout
#endif // #ifndef SPROUT_FUNCTIONAL_MULTIPLIES_HPP