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1// -*- C++ -*-2//===----------------------------------------------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___RANGES_TAKE_WHILE_VIEW_H11#define _LIBCPP___RANGES_TAKE_WHILE_VIEW_H12 13#include <__concepts/constructible.h>14#include <__concepts/convertible_to.h>15#include <__config>16#include <__functional/bind_back.h>17#include <__functional/invoke.h>18#include <__iterator/concepts.h>19#include <__memory/addressof.h>20#include <__ranges/access.h>21#include <__ranges/all.h>22#include <__ranges/concepts.h>23#include <__ranges/movable_box.h>24#include <__ranges/range_adaptor.h>25#include <__ranges/view_interface.h>26#include <__type_traits/decay.h>27#include <__type_traits/is_nothrow_constructible.h>28#include <__type_traits/is_object.h>29#include <__type_traits/maybe_const.h>30#include <__utility/forward.h>31#include <__utility/in_place.h>32#include <__utility/move.h>33 34#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)35# pragma GCC system_header36#endif37 38_LIBCPP_PUSH_MACROS39#include <__undef_macros>40 41_LIBCPP_BEGIN_NAMESPACE_STD42 43#if _LIBCPP_STD_VER >= 2044 45namespace ranges {46 47template <view _View, class _Pred>48 requires input_range<_View> && is_object_v<_Pred> && indirect_unary_predicate<const _Pred, iterator_t<_View>>49class _LIBCPP_ABI_LLVM18_NO_UNIQUE_ADDRESS take_while_view : public view_interface<take_while_view<_View, _Pred>> {50 template <bool>51 class __sentinel;52 53 _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();54 _LIBCPP_NO_UNIQUE_ADDRESS __movable_box<_Pred> __pred_;55 56public:57 _LIBCPP_HIDE_FROM_ABI take_while_view()58 requires default_initializable<_View> && default_initializable<_Pred>59 = default;60 61 _LIBCPP_HIDE_FROM_ABI constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 take_while_view(_View __base, _Pred __pred)62 : __base_(std::move(__base)), __pred_(std::in_place, std::move(__pred)) {}63 64 _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&65 requires copy_constructible<_View>66 {67 return __base_;68 }69 70 _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }71 72 _LIBCPP_HIDE_FROM_ABI constexpr const _Pred& pred() const { return *__pred_; }73 74 _LIBCPP_HIDE_FROM_ABI constexpr auto begin()75 requires(!__simple_view<_View>)76 {77 return ranges::begin(__base_);78 }79 80 _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const81 requires range<const _View> && indirect_unary_predicate<const _Pred, iterator_t<const _View>>82 {83 return ranges::begin(__base_);84 }85 86 _LIBCPP_HIDE_FROM_ABI constexpr auto end()87 requires(!__simple_view<_View>)88 {89 return __sentinel</*_Const=*/false>(ranges::end(__base_), std::addressof(*__pred_));90 }91 92 _LIBCPP_HIDE_FROM_ABI constexpr auto end() const93 requires range<const _View> && indirect_unary_predicate<const _Pred, iterator_t<const _View>>94 {95 return __sentinel</*_Const=*/true>(ranges::end(__base_), std::addressof(*__pred_));96 }97};98 99template <class _Range, class _Pred>100take_while_view(_Range&&, _Pred) -> take_while_view<views::all_t<_Range>, _Pred>;101 102template <view _View, class _Pred>103 requires input_range<_View> && is_object_v<_Pred> && indirect_unary_predicate<const _Pred, iterator_t<_View>>104template <bool _Const>105class take_while_view<_View, _Pred>::__sentinel {106 using _Base _LIBCPP_NODEBUG = __maybe_const<_Const, _View>;107 108 sentinel_t<_Base> __end_ = sentinel_t<_Base>();109 const _Pred* __pred_ = nullptr;110 111 friend class __sentinel<!_Const>;112 113public:114 _LIBCPP_HIDE_FROM_ABI __sentinel() = default;115 116 _LIBCPP_HIDE_FROM_ABI constexpr explicit __sentinel(sentinel_t<_Base> __end, const _Pred* __pred)117 : __end_(std::move(__end)), __pred_(__pred) {}118 119 _LIBCPP_HIDE_FROM_ABI constexpr __sentinel(__sentinel<!_Const> __s)120 requires _Const && convertible_to<sentinel_t<_View>, sentinel_t<_Base>>121 : __end_(std::move(__s.__end_)), __pred_(__s.__pred_) {}122 123 _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Base> base() const { return __end_; }124 125 _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const iterator_t<_Base>& __x, const __sentinel& __y) {126 return __x == __y.__end_ || !std::invoke(*__y.__pred_, *__x);127 }128 129 template <bool _OtherConst = !_Const>130 requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const<_OtherConst, _View>>>131 _LIBCPP_HIDE_FROM_ABI friend constexpr bool132 operator==(const iterator_t<__maybe_const<_OtherConst, _View>>& __x, const __sentinel& __y) {133 return __x == __y.__end_ || !std::invoke(*__y.__pred_, *__x);134 }135};136 137namespace views {138namespace __take_while {139 140struct __fn {141 template <class _Range, class _Pred>142 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range, _Pred&& __pred) const143 noexcept(noexcept(/**/ take_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))))144 -> decltype(/*--*/ take_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred))) {145 return /*-------------*/ take_while_view(std::forward<_Range>(__range), std::forward<_Pred>(__pred));146 }147 148 template <class _Pred>149 requires constructible_from<decay_t<_Pred>, _Pred>150 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Pred&& __pred) const151 noexcept(is_nothrow_constructible_v<decay_t<_Pred>, _Pred>) {152 return __pipeable(std::__bind_back(*this, std::forward<_Pred>(__pred)));153 }154};155 156} // namespace __take_while157 158inline namespace __cpo {159inline constexpr auto take_while = __take_while::__fn{};160} // namespace __cpo161} // namespace views162} // namespace ranges163 164#endif // _LIBCPP_STD_VER >= 20165 166_LIBCPP_END_NAMESPACE_STD167 168_LIBCPP_POP_MACROS169 170#endif // _LIBCPP___RANGES_TAKE_WHILE_VIEW_H171