1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
|
// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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___RANGES_REPEAT_VIEW_H
#define _LIBCPP___RANGES_REPEAT_VIEW_H
#include <__concepts/constructible.h>
#include <__concepts/same_as.h>
#include <__concepts/semiregular.h>
#include <__config>
#include <__iterator/concepts.h>
#include <__iterator/iterator_traits.h>
#include <__iterator/unreachable_sentinel.h>
#include <__memory/addressof.h>
#include <__ranges/iota_view.h>
#include <__ranges/movable_box.h>
#include <__ranges/view_interface.h>
#include <__type_traits/is_object.h>
#include <__type_traits/make_unsigned.h>
#include <__type_traits/remove_cv.h>
#include <__utility/forward.h>
#include <__utility/in_place.h>
#include <__utility/move.h>
#include <__utility/piecewise_construct.h>
#include <tuple>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER >= 23
namespace ranges {
template <class _Tp>
concept __integer_like_with_usable_difference_type =
__signed_integer_like<_Tp> || (__integer_like<_Tp> && weakly_incrementable<_Tp>);
template <class _Tp>
struct __repeat_view_iterator_difference {
using type = _IotaDiffT<_Tp>;
};
template <__signed_integer_like _Tp>
struct __repeat_view_iterator_difference<_Tp> {
using type = _Tp;
};
template <class _Tp>
using __repeat_view_iterator_difference_t = typename __repeat_view_iterator_difference<_Tp>::type;
namespace views::__drop {
struct __fn;
} // namespace views::__drop
namespace views::__take {
struct __fn;
} // namespace views::__take
template <move_constructible _Tp, semiregular _Bound = unreachable_sentinel_t>
requires(is_object_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>> &&
(__integer_like_with_usable_difference_type<_Bound> || same_as<_Bound, unreachable_sentinel_t>))
class repeat_view : public view_interface<repeat_view<_Tp, _Bound>> {
friend struct views::__take::__fn;
friend struct views::__drop::__fn;
class __iterator;
public:
_LIBCPP_HIDE_FROM_ABI repeat_view()
requires default_initializable<_Tp>
= default;
_LIBCPP_HIDE_FROM_ABI constexpr explicit repeat_view(const _Tp& __value, _Bound __bound_sentinel = _Bound())
requires copy_constructible<_Tp>
: __value_(in_place, __value), __bound_(__bound_sentinel) {
if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
_LIBCPP_ASSERT(__bound_ >= 0, "The value of bound must be greater than or equal to 0");
}
_LIBCPP_HIDE_FROM_ABI constexpr explicit repeat_view(_Tp&& __value, _Bound __bound_sentinel = _Bound())
: __value_(in_place, std::move(__value)), __bound_(__bound_sentinel) {
if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
_LIBCPP_ASSERT(__bound_ >= 0, "The value of bound must be greater than or equal to 0");
}
template <class... _TpArgs, class... _BoundArgs>
requires(constructible_from<_Tp, _TpArgs...> && constructible_from<_Bound, _BoundArgs...>)
_LIBCPP_HIDE_FROM_ABI constexpr explicit repeat_view(
piecewise_construct_t, tuple<_TpArgs...> __value_args, tuple<_BoundArgs...> __bound_args = tuple<>{})
: __value_(in_place, std::make_from_tuple<_Tp>(std::move(__value_args))),
__bound_(std::make_from_tuple<_Bound>(std::move(__bound_args))) {
if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
_LIBCPP_ASSERT(
__bound_ >= 0, "The behavior is undefined if Bound is not unreachable_sentinel_t and bound is negative");
}
_LIBCPP_HIDE_FROM_ABI constexpr __iterator begin() const { return __iterator(std::addressof(*__value_)); }
_LIBCPP_HIDE_FROM_ABI constexpr __iterator end() const
requires(!same_as<_Bound, unreachable_sentinel_t>)
{
return __iterator(std::addressof(*__value_), __bound_);
}
_LIBCPP_HIDE_FROM_ABI constexpr unreachable_sentinel_t end() const noexcept { return unreachable_sentinel; }
_LIBCPP_HIDE_FROM_ABI constexpr auto size() const
requires(!same_as<_Bound, unreachable_sentinel_t>)
{
return std::__to_unsigned_like(__bound_);
}
private:
__movable_box<_Tp> __value_;
_LIBCPP_NO_UNIQUE_ADDRESS _Bound __bound_ = _Bound();
};
template <class _Tp, class _Bound>
repeat_view(_Tp, _Bound) -> repeat_view<_Tp, _Bound>;
// [range.repeat.iterator]
template <move_constructible _Tp, semiregular _Bound>
requires(is_object_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>> &&
(__integer_like_with_usable_difference_type<_Bound> || same_as<_Bound, unreachable_sentinel_t>))
class repeat_view<_Tp, _Bound>::__iterator {
friend class repeat_view;
using _IndexT = conditional_t<same_as<_Bound, unreachable_sentinel_t>, ptrdiff_t, _Bound>;
_LIBCPP_HIDE_FROM_ABI constexpr explicit __iterator(const _Tp* __value, _IndexT __bound_sentinel = _IndexT())
: __value_(__value), __current_(__bound_sentinel) {}
public:
using iterator_concept = random_access_iterator_tag;
using iterator_category = random_access_iterator_tag;
using value_type = _Tp;
using difference_type = __repeat_view_iterator_difference_t<_IndexT>;
_LIBCPP_HIDE_FROM_ABI __iterator() = default;
_LIBCPP_HIDE_FROM_ABI constexpr const _Tp& operator*() const noexcept { return *__value_; }
_LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator++() {
++__current_;
return *this;
}
_LIBCPP_HIDE_FROM_ABI constexpr __iterator operator++(int) {
auto __tmp = *this;
++*this;
return __tmp;
}
_LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator--() {
if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
_LIBCPP_ASSERT(__current_ > 0, "The value of bound must be greater than or equal to 0");
--__current_;
return *this;
}
_LIBCPP_HIDE_FROM_ABI constexpr __iterator operator--(int) {
auto __tmp = *this;
--*this;
return __tmp;
}
_LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator+=(difference_type __n) {
if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
_LIBCPP_ASSERT(__current_ + __n >= 0, "The value of bound must be greater than or equal to 0");
__current_ += __n;
return *this;
}
_LIBCPP_HIDE_FROM_ABI constexpr __iterator& operator-=(difference_type __n) {
if constexpr (!same_as<_Bound, unreachable_sentinel_t>)
_LIBCPP_ASSERT(__current_ - __n >= 0, "The value of bound must be greater than or equal to 0");
__current_ -= __n;
return *this;
}
_LIBCPP_HIDE_FROM_ABI constexpr const _Tp& operator[](difference_type __n) const noexcept { return *(*this + __n); }
_LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __iterator& __x, const __iterator& __y) {
return __x.__current_ == __y.__current_;
}
_LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(const __iterator& __x, const __iterator& __y) {
return __x.__current_ <=> __y.__current_;
}
_LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(__iterator __i, difference_type __n) {
__i += __n;
return __i;
}
_LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator+(difference_type __n, __iterator __i) {
__i += __n;
return __i;
}
_LIBCPP_HIDE_FROM_ABI friend constexpr __iterator operator-(__iterator __i, difference_type __n) {
__i -= __n;
return __i;
}
_LIBCPP_HIDE_FROM_ABI friend constexpr difference_type operator-(const __iterator& __x, const __iterator& __y) {
return static_cast<difference_type>(__x.__current_) - static_cast<difference_type>(__y.__current_);
}
private:
const _Tp* __value_ = nullptr;
_IndexT __current_ = _IndexT();
};
// clang-format off
namespace views {
namespace __repeat {
struct __fn {
template <class _Tp>
_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __value) const
noexcept(noexcept(ranges::repeat_view(std::forward<_Tp>(__value))))
-> decltype( ranges::repeat_view(std::forward<_Tp>(__value)))
{ return ranges::repeat_view(std::forward<_Tp>(__value)); }
template <class _Tp, class _Bound>
_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __value, _Bound&& __bound_sentinel) const
noexcept(noexcept(ranges::repeat_view(std::forward<_Tp>(__value), std::forward<_Bound>(__bound_sentinel))))
-> decltype( ranges::repeat_view(std::forward<_Tp>(__value), std::forward<_Bound>(__bound_sentinel)))
{ return ranges::repeat_view(std::forward<_Tp>(__value), std::forward<_Bound>(__bound_sentinel)); }
};
} // namespace __repeat
// clang-format on
inline namespace __cpo {
inline constexpr auto repeat = __repeat::__fn{};
} // namespace __cpo
} // namespace views
template <class _Tp>
inline constexpr bool __is_repeat_specialization = false;
template <class _Tp, class _Bound>
inline constexpr bool __is_repeat_specialization<repeat_view<_Tp, _Bound>> = true;
} // namespace ranges
#endif // _LIBCPP_STD_VER >= 23
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___RANGES_REPEAT_VIEW_H
|
