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ZijunZhaoCCKZijunZhaoCCK
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[libc++] Implement ranges::starts_with
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‎libcxx/include/CMakeLists.txt

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@@ -166,6 +166,7 @@ set(files
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__algorithm/ranges_sort_heap.h
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__algorithm/ranges_stable_partition.h
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__algorithm/ranges_stable_sort.h
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__algorithm/ranges_starts_with.h
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__algorithm/ranges_swap_ranges.h
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__algorithm/ranges_transform.h
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__algorithm/ranges_unique.h

‎libcxx/include/__algorithm/ranges_starts_with.h

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//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef _LIBCPP___ALGORITHM_RANGES_STARTS_WITH_H
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#define _LIBCPP___ALGORITHM_RANGES_STARTS_WITH_H
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#include "ranges_mismatch.h"
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#include <__algorithm/in_in_result.h>
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#include <__config>
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#include <__functional/identity.h>
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#include <__functional/ranges_operations.h>
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#include <__iterator/concepts.h>
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#include <__iterator/indirectly_comparable.h>
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#include <__ranges/access.h>
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#include <__ranges/concepts.h>
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#include <__utility/move.h>
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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
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# pragma GCC system_header
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#endif
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#if _LIBCPP_STD_VER >= 23
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_LIBCPP_BEGIN_NAMESPACE_STD
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namespace ranges {
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namespace __starts_with {
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struct __fn {
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template <input_iterator _Iter1,
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sentinel_for<_Iter1> _Sent1,
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input_iterator _Iter2,
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sentinel_for<_Iter2> _Sent2,
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class _Pred = ranges::equal_to,
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class _Proj1 = identity,
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class _Proj2 = identity>
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requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
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_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
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_Iter1 __first1,
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_Sent1 __last1,
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_Iter2 __first2,
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_Sent2 __last2,
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_Pred __pred = {},
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_Proj1 __proj1 = {},
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_Proj2 __proj2 = {}) const {
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return __mismatch::__fn::__go(
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std::move(__first1),
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std::move(__last1),
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std::move(__first2),
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std::move(__last2),
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__pred,
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__proj1,
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__proj2)
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.in2 == __last2;
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}
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template <input_range _Range1,
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input_range _Range2,
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class _Pred = ranges::equal_to,
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class _Proj1 = identity,
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class _Proj2 = identity>
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requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
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_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
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_Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
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return __mismatch::__fn::__go(
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ranges::begin(__range1),
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ranges::end(__range1),
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ranges::begin(__range2),
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ranges::end(__range2),
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__pred,
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__proj1,
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__proj2)
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.in2 == ranges::end(__range2);
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}
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};
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} // namespace __starts_with
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inline namespace __cpo {
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inline constexpr auto starts_with = __starts_with::__fn{};
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} // namespace __cpo
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} // namespace ranges
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_LIBCPP_END_NAMESPACE_STD
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#endif // _LIBCPP_STD_VER >= 23
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#endif // _LIBCPP___ALGORITHM_RANGES_STARTS_WITH_H

‎libcxx/include/algorithm

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@@ -446,6 +446,18 @@ namespace ranges {
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indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
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constexpr bool ranges::none_of(R&& r, Pred pred, Proj proj = {}); // since C++20
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template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
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class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
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requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
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constexpr bool ranges::starts_with(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
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Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++23
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template<input_range R1, input_range R2, class Pred = ranges::equal_to, class Proj1 = identity,
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class Proj2 = identity>
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requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
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constexpr bool ranges::starts_with(R1&& r1, R2&& r2, Pred pred = {},
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Proj1 proj1 = {}, Proj2 proj2 = {}); // since C++23
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template<input_iterator I1, sentinel_for<I1> S1,
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random_access_iterator I2, sentinel_for<I2> S2,
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class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
@@ -1874,6 +1886,7 @@ template <class BidirectionalIterator, class Compare>
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#include <__algorithm/ranges_sort_heap.h>
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#include <__algorithm/ranges_stable_partition.h>
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#include <__algorithm/ranges_stable_sort.h>
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#include <__algorithm/ranges_starts_with.h>
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#include <__algorithm/ranges_swap_ranges.h>
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#include <__algorithm/ranges_transform.h>
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#include <__algorithm/ranges_unique.h>

‎libcxx/include/module.modulemap.in

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@@ -578,6 +578,7 @@ module std [system] {
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private header "__algorithm/ranges_stable_sort.h"
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export functional.__functional.ranges_operations
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}
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module ranges_starts_with { private header "__algorithm/ranges_starts_with.h" }
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module ranges_swap_ranges {
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private header "__algorithm/ranges_swap_ranges.h"
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export algorithm.__algorithm.in_in_result

‎libcxx/test/libcxx/algorithms/ranges_robust_against_copying_comparators.pass.cpp

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@@ -215,7 +215,8 @@ constexpr bool all_the_algorithms()
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if (!std::is_constant_evaluated()) { (void)std::ranges::stable_sort(first, last, Less(&copies)); assert(copies == 0); }
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if (!std::is_constant_evaluated()) { (void)std::ranges::stable_sort(a, Less(&copies)); assert(copies == 0); }
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#if TEST_STD_VER > 20
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//(void)std::ranges::starts_with(first, last, first2, last2, Equal(&copies)); assert(copies == 0);
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(void)std::ranges::starts_with(first, last, first2, last2, Equal(&copies)); assert(copies == 0);
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(void)std::ranges::starts_with(a, b, Equal(&copies)); assert(copies == 0);
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#endif
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(void)std::ranges::transform(first, last, first2, UnaryTransform(&copies)); assert(copies == 0);
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(void)std::ranges::transform(a, first2, UnaryTransform(&copies)); assert(copies == 0);

‎libcxx/test/libcxx/algorithms/ranges_robust_against_copying_projections.pass.cpp

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@@ -206,7 +206,8 @@ constexpr bool all_the_algorithms()
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if (!std::is_constant_evaluated()) { (void)std::ranges::stable_sort(first, last, Less(), Proj(&copies)); assert(copies == 0); }
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if (!std::is_constant_evaluated()) { (void)std::ranges::stable_sort(a, Less(), Proj(&copies)); assert(copies == 0); }
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#if TEST_STD_VER > 20
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//(void)std::ranges::starts_with(first, last, first2, last2, Equal(), Proj(&copies), Proj(&copies)); assert(copies == 0);
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(void)std::ranges::starts_with(first, last, first2, last2, Equal(), Proj(&copies), Proj(&copies)); assert(copies == 0);
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(void)std::ranges::starts_with(a, b, Equal(), Proj(&copies), Proj(&copies)); assert(copies == 0);
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#endif
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(void)std::ranges::transform(first, last, first2, UnaryTransform(), Proj(&copies)); assert(copies == 0);
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(void)std::ranges::transform(a, first2, UnaryTransform(), Proj(&copies)); assert(copies == 0);

‎libcxx/test/libcxx/private_headers.verify.cpp

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#include <__algorithm/ranges_sort_heap.h> // expected-error@*:* {{use of private header from outside its module: '__algorithm/ranges_sort_heap.h'}}
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#include <__algorithm/ranges_stable_partition.h> // expected-error@*:* {{use of private header from outside its module: '__algorithm/ranges_stable_partition.h'}}
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#include <__algorithm/ranges_stable_sort.h> // expected-error@*:* {{use of private header from outside its module: '__algorithm/ranges_stable_sort.h'}}
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#include <__algorithm/ranges_starts_with.h> // expected-error@*:* {{use of private header from outside its module: '__algorithm/ranges_starts_with.h'}}
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#include <__algorithm/ranges_swap_ranges.h> // expected-error@*:* {{use of private header from outside its module: '__algorithm/ranges_swap_ranges.h'}}
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#include <__algorithm/ranges_transform.h> // expected-error@*:* {{use of private header from outside its module: '__algorithm/ranges_transform.h'}}
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#include <__algorithm/ranges_unique.h> // expected-error@*:* {{use of private header from outside its module: '__algorithm/ranges_unique.h'}}

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