Sprout/sprout/functional/logical_not.hpp
2014-08-14 22:55:49 +09:00

43 lines
1.2 KiB
C++

/*=============================================================================
Copyright (c) 2011-2014 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_LOGICAL_NOT_HPP
#define SPROUT_FUNCTIONAL_LOGICAL_NOT_HPP
#include <utility>
#include <sprout/config.hpp>
#include <sprout/utility/forward.hpp>
namespace sprout {
// 20.8.6 logical operations
template<typename T = void>
struct logical_not {
public:
typedef T argument_type;
typedef bool result_type;
public:
SPROUT_CONSTEXPR bool operator()(T const& x) const {
return !x;
}
};
template<>
struct logical_not<void> {
public:
typedef void is_transparent;
public:
template<typename T>
SPROUT_CONSTEXPR decltype(!std::declval<T>())
operator()(T&& x)
const SPROUT_NOEXCEPT_IF_EXPR(!std::declval<T>())
{
return !SPROUT_FORWARD(T, x);
}
};
} // namespace sprout
#endif // #ifndef SPROUT_FUNCTIONAL_LOGICAL_NOT_HPP