audio_trans/lib/inc/drogon/utils/optional.h

32 lines
620 B
C++

/**
*
* optional.h
* An Tao
*
* Copyright 2018, An Tao. All rights reserved.
* https://github.com/an-tao/drogon
* Use of this source code is governed by a MIT license
* that can be found in the License file.
*
* Drogon
*
*/
#pragma once
#if __cplusplus >= 201703L || (defined _MSC_VER && _MSC_VER > 1900)
#include <optional>
#else
#include <boost/optional.hpp>
#endif
namespace drogon
{
#if __cplusplus >= 201703L || (defined _MSC_VER && _MSC_VER > 1900)
using std::nullopt;
using std::optional;
#else
const boost::none_t nullopt = boost::none;
using boost::optional;
#endif
} // namespace drogon