llvm-project/libcxx/include/__utility/as_const.h

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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___UTILITY_AS_CONST_H
#define _LIBCPP___UTILITY_AS_CONST_H
#include <__config>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER > 14
template <class _Tp>
_LIBCPP_NODISCARD_EXT constexpr add_const_t<_Tp>& as_const(_Tp& __t) noexcept { return __t; }
template <class _Tp>
void as_const(const _Tp&&) = delete;
#endif
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP___UTILITY_AS_CONST_H