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___ALGORITHM_RANGES_LEXICOGRAPHICAL_COMPARE_H 10 #define _LIBCPP___ALGORITHM_RANGES_LEXICOGRAPHICAL_COMPARE_H 11 12 #include <__config> 13 #include <__functional/identity.h> 14 #include <__functional/invoke.h> 15 #include <__functional/ranges_operations.h> 16 #include <__iterator/concepts.h> 17 #include <__iterator/projected.h> 18 #include <__ranges/access.h> 19 #include <__ranges/concepts.h> 20 #include <__utility/move.h> 21 22 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 23 # pragma GCC system_header 24 #endif 25 26 #if _LIBCPP_STD_VER >= 20 27 28 _LIBCPP_BEGIN_NAMESPACE_STD 29 30 namespace ranges { 31 namespace __lexicographical_compare { 32 struct __fn { 33 template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Proj1, class _Proj2, class _Comp> 34 _LIBCPP_HIDE_FROM_ABI constexpr static bool __lexicographical_compare_impl( 35 _Iter1 __first1, 36 _Sent1 __last1, 37 _Iter2 __first2, 38 _Sent2 __last2, 39 _Comp& __comp, 40 _Proj1& __proj1, 41 _Proj2& __proj2) { 42 while (__first2 != __last2) { 43 if (__first1 == __last1 || std::invoke(__comp, std::invoke(__proj1, *__first1), std::invoke(__proj2, *__first2))) 44 return true; 45 if (std::invoke(__comp, std::invoke(__proj2, *__first2), std::invoke(__proj1, *__first1))) 46 return false; 47 ++__first1; 48 ++__first2; 49 } 50 return false; 51 } 52 53 template <input_iterator _Iter1, 54 sentinel_for<_Iter1> _Sent1, 55 input_iterator _Iter2, 56 sentinel_for<_Iter2> _Sent2, 57 class _Proj1 = identity, 58 class _Proj2 = identity, 59 indirect_strict_weak_order<projected<_Iter1, _Proj1>, projected<_Iter2, _Proj2>> _Comp = ranges::less> 60 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr bool operator()( 61 _Iter1 __first1, 62 _Sent1 __last1, 63 _Iter2 __first2, 64 _Sent2 __last2, 65 _Comp __comp = {}, 66 _Proj1 __proj1 = {}, 67 _Proj2 __proj2 = {}) const { 68 return __lexicographical_compare_impl( 69 std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __comp, __proj1, __proj2); 70 } 71 72 template <input_range _Range1, 73 input_range _Range2, 74 class _Proj1 = identity, 75 class _Proj2 = identity, 76 indirect_strict_weak_order<projected<iterator_t<_Range1>, _Proj1>, projected<iterator_t<_Range2>, _Proj2>> 77 _Comp = ranges::less> 78 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr bool operator()( 79 _Range1&& __range1, _Range2&& __range2, _Comp __comp = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const { 80 return __lexicographical_compare_impl( 81 ranges::begin(__range1), 82 ranges::end(__range1), 83 ranges::begin(__range2), 84 ranges::end(__range2), 85 __comp, 86 __proj1, 87 __proj2); 88 } 89 }; 90 } // namespace __lexicographical_compare 91 92 inline namespace __cpo { 93 inline constexpr auto lexicographical_compare = __lexicographical_compare::__fn{}; 94 } // namespace __cpo 95 } // namespace ranges 96 97 _LIBCPP_END_NAMESPACE_STD 98 99 #endif // _LIBCPP_STD_VER >= 20 100 101 #endif // _LIBCPP___ALGORITHM_RANGES_LEXICOGRAPHICAL_COMPARE_H 102