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1// -*- C++ -*-2//===----------------------------------------------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___UTILITY_FORWARD_H11#define _LIBCPP___UTILITY_FORWARD_H12 13#include <__config>14#include <__type_traits/is_reference.h>15#include <__type_traits/remove_reference.h>16 17#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)18# pragma GCC system_header19#endif20 21_LIBCPP_BEGIN_NAMESPACE_STD22 23template <class _Tp>24[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp&&25forward(_LIBCPP_LIFETIMEBOUND __libcpp_remove_reference_t<_Tp>& __t) _NOEXCEPT {26 return static_cast<_Tp&&>(__t);27}28 29template <class _Tp>30[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp&&31forward(_LIBCPP_LIFETIMEBOUND __libcpp_remove_reference_t<_Tp>&& __t) _NOEXCEPT {32 static_assert(!is_lvalue_reference<_Tp>::value, "cannot forward an rvalue as an lvalue");33 return static_cast<_Tp&&>(__t);34}35 36_LIBCPP_END_NAMESPACE_STD37 38#endif // _LIBCPP___UTILITY_FORWARD_H39