Sprout/sprout/functional/negate.hpp
2012-10-25 12:50:03 +09:00

36 lines
803 B
C++

#ifndef SPROUT_FUNCTIONAL_NEGATE_HPP
#define SPROUT_FUNCTIONAL_NEGATE_HPP
#include <utility>
#include <sprout/config.hpp>
#include <sprout/utility/forward.hpp>
namespace sprout {
// Copyright (C) 2011 RiSK (sscrisk)
// 20.8.4 Arithmetic operations
template<typename T = void>
struct negate {
public:
typedef T argument_type;
typedef T result_type;
public:
SPROUT_CONSTEXPR T operator()(T const& x) const {
return -x;
}
};
template<>
struct negate<void> {
public:
template<typename T>
SPROUT_CONSTEXPR decltype(-std::declval<T>())
operator()(T&& x)
const SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(-std::declval<T>()))
{
return -sprout::forward<T>(x);
}
};
} // namespace sprout
#endif // #ifndef SPROUT_FUNCTIONAL_NEGATE_HPP