106c3fb27SDimitry Andric //===----------------------------------------------------------------------===// 206c3fb27SDimitry Andric // 306c3fb27SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 406c3fb27SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 506c3fb27SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 606c3fb27SDimitry Andric // 706c3fb27SDimitry Andric //===----------------------------------------------------------------------===// 806c3fb27SDimitry Andric 906c3fb27SDimitry Andric #ifndef _LIBCPP___TUPLE_TUPLE_ELEMENT_H 1006c3fb27SDimitry Andric #define _LIBCPP___TUPLE_TUPLE_ELEMENT_H 1106c3fb27SDimitry Andric 1206c3fb27SDimitry Andric #include <__config> 1306c3fb27SDimitry Andric #include <__tuple/tuple_indices.h> 1406c3fb27SDimitry Andric #include <__tuple/tuple_types.h> 1506c3fb27SDimitry Andric #include <cstddef> 1606c3fb27SDimitry Andric 1706c3fb27SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 1806c3fb27SDimitry Andric # pragma GCC system_header 1906c3fb27SDimitry Andric #endif 2006c3fb27SDimitry Andric 2106c3fb27SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 2206c3fb27SDimitry Andric 23cb14a3feSDimitry Andric template <size_t _Ip, class _Tp> 24cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_element; 2506c3fb27SDimitry Andric 2606c3fb27SDimitry Andric template <size_t _Ip, class _Tp> 27cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, const _Tp> { 280fca6ea1SDimitry Andric typedef _LIBCPP_NODEBUG const typename tuple_element<_Ip, _Tp>::type type; 2906c3fb27SDimitry Andric }; 3006c3fb27SDimitry Andric 3106c3fb27SDimitry Andric template <size_t _Ip, class _Tp> 32cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, volatile _Tp> { 330fca6ea1SDimitry Andric typedef _LIBCPP_NODEBUG volatile typename tuple_element<_Ip, _Tp>::type type; 3406c3fb27SDimitry Andric }; 3506c3fb27SDimitry Andric 3606c3fb27SDimitry Andric template <size_t _Ip, class _Tp> 37cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, const volatile _Tp> { 380fca6ea1SDimitry Andric typedef _LIBCPP_NODEBUG const volatile typename tuple_element<_Ip, _Tp>::type type; 3906c3fb27SDimitry Andric }; 4006c3fb27SDimitry Andric 4106c3fb27SDimitry Andric #ifndef _LIBCPP_CXX03_LANG 4206c3fb27SDimitry Andric 43*2f2ebe75SDimitry Andric # if !__has_builtin(__type_pack_element) 44*2f2ebe75SDimitry Andric 45*2f2ebe75SDimitry Andric namespace __indexer_detail { 46*2f2ebe75SDimitry Andric 47*2f2ebe75SDimitry Andric template <size_t _Idx, class _Tp> 48*2f2ebe75SDimitry Andric struct __indexed { 49*2f2ebe75SDimitry Andric using type _LIBCPP_NODEBUG = _Tp; 50*2f2ebe75SDimitry Andric }; 51*2f2ebe75SDimitry Andric 52*2f2ebe75SDimitry Andric template <class _Types, class _Indexes> 53*2f2ebe75SDimitry Andric struct __indexer; 54*2f2ebe75SDimitry Andric 55*2f2ebe75SDimitry Andric template <class... _Types, size_t... _Idx> 56*2f2ebe75SDimitry Andric struct __indexer<__tuple_types<_Types...>, __tuple_indices<_Idx...>> : __indexed<_Idx, _Types>... {}; 57*2f2ebe75SDimitry Andric 58*2f2ebe75SDimitry Andric template <size_t _Idx, class _Tp> 59*2f2ebe75SDimitry Andric __indexed<_Idx, _Tp> __at_index(__indexed<_Idx, _Tp> const&); 60*2f2ebe75SDimitry Andric 61*2f2ebe75SDimitry Andric } // namespace __indexer_detail 62*2f2ebe75SDimitry Andric 63*2f2ebe75SDimitry Andric template <size_t _Idx, class... _Types> 64*2f2ebe75SDimitry Andric using __type_pack_element _LIBCPP_NODEBUG = typename decltype(__indexer_detail::__at_index<_Idx>( 65*2f2ebe75SDimitry Andric __indexer_detail::__indexer< __tuple_types<_Types...>, 66*2f2ebe75SDimitry Andric typename __make_tuple_indices<sizeof...(_Types)>::type >{}))::type; 67*2f2ebe75SDimitry Andric # endif 68*2f2ebe75SDimitry Andric 6906c3fb27SDimitry Andric template <size_t _Ip, class... _Types> 70cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, __tuple_types<_Types...> > { 7106c3fb27SDimitry Andric static_assert(_Ip < sizeof...(_Types), "tuple_element index out of range"); 7206c3fb27SDimitry Andric typedef _LIBCPP_NODEBUG __type_pack_element<_Ip, _Types...> type; 7306c3fb27SDimitry Andric }; 7406c3fb27SDimitry Andric 7506c3fb27SDimitry Andric # if _LIBCPP_STD_VER >= 14 7606c3fb27SDimitry Andric template <size_t _Ip, class... _Tp> 7706c3fb27SDimitry Andric using tuple_element_t _LIBCPP_NODEBUG = typename tuple_element<_Ip, _Tp...>::type; 7806c3fb27SDimitry Andric # endif 7906c3fb27SDimitry Andric 8006c3fb27SDimitry Andric #endif // _LIBCPP_CXX03_LANG 8106c3fb27SDimitry Andric 8206c3fb27SDimitry Andric _LIBCPP_END_NAMESPACE_STD 8306c3fb27SDimitry Andric 8406c3fb27SDimitry Andric #endif // _LIBCPP___TUPLE_TUPLE_ELEMENT_H 85