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-rw-r--r--contrib/llvm-project/libcxx/include/__algorithm/ranges_minmax.h133
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diff --git a/contrib/llvm-project/libcxx/include/__algorithm/ranges_minmax.h b/contrib/llvm-project/libcxx/include/__algorithm/ranges_minmax.h
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@@ -0,0 +1,133 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_RANGES_MINMAX_H
+#define _LIBCPP___ALGORITHM_RANGES_MINMAX_H
+
+#include <__algorithm/min_max_result.h>
+#include <__algorithm/minmax_element.h>
+#include <__assert>
+#include <__concepts/copyable.h>
+#include <__config>
+#include <__functional/identity.h>
+#include <__functional/invoke.h>
+#include <__functional/ranges_operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/projected.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+template <class _T1>
+using minmax_result = min_max_result<_T1>;
+
+namespace __minmax {
+struct __fn {
+ template <class _Type, class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Type*, _Proj>> _Comp = ranges::less>
+ _LIBCPP_HIDE_FROM_ABI constexpr ranges::minmax_result<const _Type&>
+ operator()(const _Type& __a, const _Type& __b, _Comp __comp = {}, _Proj __proj = {}) const {
+ if (std::invoke(__comp, std::invoke(__proj, __b), std::invoke(__proj, __a)))
+ return {__b, __a};
+ return {__a, __b};
+ }
+
+ template <copyable _Type, class _Proj = identity,
+ indirect_strict_weak_order<projected<const _Type*, _Proj>> _Comp = ranges::less>
+ _LIBCPP_HIDE_FROM_ABI constexpr
+ ranges::minmax_result<_Type> operator()(initializer_list<_Type> __il, _Comp __comp = {}, _Proj __proj = {}) const {
+ _LIBCPP_ASSERT(__il.begin() != __il.end(), "initializer_list has to contain at least one element");
+ auto __iters = std::__minmax_element_impl(__il.begin(), __il.end(), __comp, __proj);
+ return ranges::minmax_result<_Type> { *__iters.first, *__iters.second };
+ }
+
+ template <input_range _Range, class _Proj = identity,
+ indirect_strict_weak_order<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::less>
+ requires indirectly_copyable_storable<iterator_t<_Range>, range_value_t<_Range>*>
+ _LIBCPP_HIDE_FROM_ABI constexpr
+ ranges::minmax_result<range_value_t<_Range>> operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
+ auto __first = ranges::begin(__r);
+ auto __last = ranges::end(__r);
+ using _ValueT = range_value_t<_Range>;
+
+ _LIBCPP_ASSERT(__first != __last, "range has to contain at least one element");
+
+ if constexpr (forward_range<_Range>) {
+ auto __result = std::__minmax_element_impl(__first, __last, __comp, __proj);
+ return {*__result.first, *__result.second};
+ } else {
+ // input_iterators can't be copied, so the implementation for input_iterators has to store
+ // the values instead of a pointer to the correct values
+ auto __less = [&](auto&& __a, auto&& __b) -> bool {
+ return std::invoke(__comp, std::invoke(__proj, std::forward<decltype(__a)>(__a)),
+ std::invoke(__proj, std::forward<decltype(__b)>(__b)));
+ };
+
+ ranges::minmax_result<_ValueT> __result = {*__first, __result.min};
+ if (__first == __last || ++__first == __last)
+ return __result;
+
+ if (__less(*__first, __result.min))
+ __result.min = *__first;
+ else
+ __result.max = *__first;
+
+ while (++__first != __last) {
+ _ValueT __i = *__first;
+ if (++__first == __last) {
+ if (__less(__i, __result.min))
+ __result.min = __i;
+ else if (!__less(__i, __result.max))
+ __result.max = __i;
+ return __result;
+ }
+
+ if (__less(*__first, __i)) {
+ if (__less(*__first, __result.min))
+ __result.min = *__first;
+ if (!__less(__i, __result.max))
+ __result.max = std::move(__i);
+ } else {
+ if (__less(__i, __result.min))
+ __result.min = std::move(__i);
+ if (!__less(*__first, __result.max))
+ __result.max = *__first;
+ }
+ }
+ return __result;
+ }
+ }
+};
+} // namespace __minmax
+
+inline namespace __cpo {
+ inline constexpr auto minmax = __minmax::__fn{};
+} // namespace __cpo
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
+
+#endif // _LIBCPP___ALGORITHM_RANGES_MINMAX_H