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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___TYPE_TRAITS_TYPE_LIST_H 10 #define _LIBCPP___TYPE_TRAITS_TYPE_LIST_H 11 12 #include <__config> 13 #include <cstddef> 14 15 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 16 # pragma GCC system_header 17 #endif 18 19 _LIBCPP_BEGIN_NAMESPACE_STD 20 21 template <class _Hp, class _Tp> 22 struct __type_list { 23 typedef _Hp _Head; 24 typedef _Tp _Tail; 25 }; 26 27 template <class _TypeList, size_t _Size, bool = _Size <= sizeof(typename _TypeList::_Head)> 28 struct __find_first; 29 30 template <class _Hp, class _Tp, size_t _Size> 31 struct __find_first<__type_list<_Hp, _Tp>, _Size, true> { 32 typedef _LIBCPP_NODEBUG _Hp type; 33 }; 34 35 template <class _Hp, class _Tp, size_t _Size> 36 struct __find_first<__type_list<_Hp, _Tp>, _Size, false> { 37 typedef _LIBCPP_NODEBUG typename __find_first<_Tp, _Size>::type type; 38 }; 39 40 _LIBCPP_END_NAMESPACE_STD 41 42 #endif // _LIBCPP___TYPE_TRAITS_TYPE_LIST_H 43