forked from etc/pineapple-src
62 lines
1.2 KiB
C++
62 lines
1.2 KiB
C++
|
/*
|
||
|
|
Copyright 2021 Glen Joseph Fernandes
|
||
|
|
(glenjofe@gmail.com)
|
||
|
|
|
||
|
|
Distributed under the Boost Software License, Version 1.0.
|
||
|
|
(http://www.boost.org/LICENSE_1_0.txt)
|
||
|
|
*/
|
||
|
|
#ifndef BOOST_FUNCTIONAL_IDENTITY_HPP
|
||
|
|
#define BOOST_FUNCTIONAL_IDENTITY_HPP
|
||
|
|
|
||
|
|
#include <boost/config.hpp>
|
||
|
|
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
|
||
|
|
#include <utility>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
namespace boost {
|
||
|
|
|
||
|
|
struct identity {
|
||
|
|
typedef void is_transparent;
|
||
|
|
|
||
|
|
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
|
||
|
|
template<class T>
|
||
|
|
BOOST_CONSTEXPR T&& operator()(T&& value) const BOOST_NOEXCEPT {
|
||
|
|
return std::forward<T>(value);
|
||
|
|
}
|
||
|
|
#else
|
||
|
|
template<class T>
|
||
|
|
BOOST_CONSTEXPR const T& operator()(const T& value) const BOOST_NOEXCEPT {
|
||
|
|
return value;
|
||
|
|
}
|
||
|
|
|
||
|
|
template<class T>
|
||
|
|
BOOST_CONSTEXPR T& operator()(T& value) const BOOST_NOEXCEPT {
|
||
|
|
return value;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
template<class>
|
||
|
|
struct result { };
|
||
|
|
|
||
|
|
template<class T>
|
||
|
|
struct result<identity(T&)> {
|
||
|
|
typedef T& type;
|
||
|
|
};
|
||
|
|
|
||
|
|
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
|
||
|
|
template<class T>
|
||
|
|
struct result<identity(T)> {
|
||
|
|
typedef T&& type;
|
||
|
|
};
|
||
|
|
|
||
|
|
template<class T>
|
||
|
|
struct result<identity(T&&)> {
|
||
|
|
typedef T&& type;
|
||
|
|
};
|
||
|
|
#endif
|
||
|
|
};
|
||
|
|
|
||
|
|
} // boost
|
||
|
|
|
||
|
|
#endif
|