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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___TUPLE_TUPLE_ELEMENT_H10#define _LIBCPP___TUPLE_TUPLE_ELEMENT_H11 12#include <__config>13#include <__cstddef/size_t.h>14 15#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)16# pragma GCC system_header17#endif18 19_LIBCPP_BEGIN_NAMESPACE_STD20 21template <size_t _Ip, class _Tp>22struct tuple_element;23 24template <size_t _Ip, class _Tp>25struct tuple_element<_Ip, const _Tp> {26 using type _LIBCPP_NODEBUG = const typename tuple_element<_Ip, _Tp>::type;27};28 29template <size_t _Ip, class _Tp>30struct tuple_element<_Ip, volatile _Tp> {31 using type _LIBCPP_NODEBUG = volatile typename tuple_element<_Ip, _Tp>::type;32};33 34template <size_t _Ip, class _Tp>35struct tuple_element<_Ip, const volatile _Tp> {36 using type _LIBCPP_NODEBUG = const volatile typename tuple_element<_Ip, _Tp>::type;37};38 39# if _LIBCPP_STD_VER >= 1440template <size_t _Ip, class... _Tp>41using tuple_element_t _LIBCPP_NODEBUG = typename tuple_element<_Ip, _Tp...>::type;42# endif43 44_LIBCPP_END_NAMESPACE_STD45 46#endif // _LIBCPP___TUPLE_TUPLE_ELEMENT_H47