master
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-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP___ITERATOR_WRAP_ITER_H
11#define _LIBCPP___ITERATOR_WRAP_ITER_H
12
13#include <__compare/ordering.h>
14#include <__compare/three_way_comparable.h>
15#include <__config>
16#include <__cstddef/size_t.h>
17#include <__iterator/iterator_traits.h>
18#include <__memory/addressof.h>
19#include <__memory/pointer_traits.h>
20#include <__type_traits/conjunction.h>
21#include <__type_traits/disjunction.h>
22#include <__type_traits/enable_if.h>
23#include <__type_traits/integral_constant.h>
24#include <__type_traits/is_convertible.h>
25#include <__type_traits/is_same.h>
26#include <__type_traits/make_const_lvalue_ref.h>
27
28#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
29# pragma GCC system_header
30#endif
31
32_LIBCPP_BEGIN_NAMESPACE_STD
33
34template <class _Iter>
35class __wrap_iter {
36public:
37 typedef _Iter iterator_type;
38 typedef typename iterator_traits<iterator_type>::value_type value_type;
39 typedef typename iterator_traits<iterator_type>::difference_type difference_type;
40 typedef typename iterator_traits<iterator_type>::pointer pointer;
41 typedef typename iterator_traits<iterator_type>::reference reference;
42 typedef typename iterator_traits<iterator_type>::iterator_category iterator_category;
43#if _LIBCPP_STD_VER >= 20
44 typedef contiguous_iterator_tag iterator_concept;
45#endif
46
47private:
48 iterator_type __i_;
49
50public:
51 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter() _NOEXCEPT : __i_() {}
52 template <
53 class _OtherIter,
54 __enable_if_t< _And< is_convertible<const _OtherIter&, _Iter>,
55 _Or<is_same<reference, __iter_reference<_OtherIter> >,
56 is_same<reference, __make_const_lvalue_ref<__iter_reference<_OtherIter> > > > >::value,
57 int> = 0>
58 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter(const __wrap_iter<_OtherIter>& __u) _NOEXCEPT
59 : __i_(__u.__i_) {}
60 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator*() const _NOEXCEPT { return *__i_; }
61 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pointer operator->() const _NOEXCEPT {
62 return std::__to_address(__i_);
63 }
64 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator++() _NOEXCEPT {
65 ++__i_;
66 return *this;
67 }
68 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator++(int) _NOEXCEPT {
69 __wrap_iter __tmp(*this);
70 ++(*this);
71 return __tmp;
72 }
73
74 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator--() _NOEXCEPT {
75 --__i_;
76 return *this;
77 }
78 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator--(int) _NOEXCEPT {
79 __wrap_iter __tmp(*this);
80 --(*this);
81 return __tmp;
82 }
83 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator+(difference_type __n) const _NOEXCEPT {
84 __wrap_iter __w(*this);
85 __w += __n;
86 return __w;
87 }
88 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator+=(difference_type __n) _NOEXCEPT {
89 __i_ += __n;
90 return *this;
91 }
92 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator-(difference_type __n) const _NOEXCEPT {
93 return *this + (-__n);
94 }
95 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator-=(difference_type __n) _NOEXCEPT {
96 *this += -__n;
97 return *this;
98 }
99 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator[](difference_type __n) const _NOEXCEPT {
100 return __i_[__n];
101 }
102
103 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 iterator_type base() const _NOEXCEPT { return __i_; }
104
105private:
106 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __wrap_iter(iterator_type __x) _NOEXCEPT : __i_(__x) {}
107
108 template <class _Up>
109 friend class __wrap_iter;
110 template <class _CharT, class _Traits, class _Alloc>
111 friend class basic_string;
112 template <class _CharT, class _Traits>
113 friend class basic_string_view;
114 template <class _Tp, class _Alloc>
115 friend class vector;
116 template <class _Tp, size_t>
117 friend class span;
118 template <class _Tp, size_t _Size>
119 friend struct array;
120};
121
122template <class _Iter1>
123_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
124operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
125 return __x.base() == __y.base();
126}
127
128template <class _Iter1, class _Iter2>
129_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
130operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
131 return __x.base() == __y.base();
132}
133
134template <class _Iter1>
135_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
136operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
137 return __x.base() < __y.base();
138}
139
140template <class _Iter1, class _Iter2>
141_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
142operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
143 return __x.base() < __y.base();
144}
145
146#if _LIBCPP_STD_VER <= 17
147template <class _Iter1>
148_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
149operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
150 return !(__x == __y);
151}
152
153template <class _Iter1, class _Iter2>
154_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
155operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
156 return !(__x == __y);
157}
158template <class _Iter1>
159_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
160operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
161 return __y < __x;
162}
163
164template <class _Iter1, class _Iter2>
165_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
166operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
167 return __y < __x;
168}
169
170template <class _Iter1>
171_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
172operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
173 return !(__x < __y);
174}
175
176template <class _Iter1, class _Iter2>
177_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
178operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
179 return !(__x < __y);
180}
181
182template <class _Iter1>
183_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
184operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
185 return !(__y < __x);
186}
187
188template <class _Iter1, class _Iter2>
189_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
190operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
191 return !(__y < __x);
192}
193
194#else
195template <class _Iter1, class _Iter2>
196_LIBCPP_HIDE_FROM_ABI constexpr strong_ordering
197operator<=>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) noexcept {
198 if constexpr (three_way_comparable_with<_Iter1, _Iter2, strong_ordering>) {
199 return __x.base() <=> __y.base();
200 } else {
201 if (__x.base() < __y.base())
202 return strong_ordering::less;
203
204 if (__x.base() == __y.base())
205 return strong_ordering::equal;
206
207 return strong_ordering::greater;
208 }
209}
210#endif // _LIBCPP_STD_VER >= 20
211
212template <class _Iter1, class _Iter2>
213_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
214#ifndef _LIBCPP_CXX03_LANG
215 auto
216 operator-(const __wrap_iter<_Iter1>& __x,
217 const __wrap_iter<_Iter2>& __y) _NOEXCEPT->decltype(__x.base() - __y.base())
218#else
219typename __wrap_iter<_Iter1>::difference_type
220operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
221#endif // C++03
222{
223 return __x.base() - __y.base();
224}
225
226template <class _Iter1>
227_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter<_Iter1>
228operator+(typename __wrap_iter<_Iter1>::difference_type __n, __wrap_iter<_Iter1> __x) _NOEXCEPT {
229 __x += __n;
230 return __x;
231}
232
233#if _LIBCPP_STD_VER <= 17
234template <class _It>
235struct __libcpp_is_contiguous_iterator<__wrap_iter<_It> > : true_type {};
236#endif
237
238template <class _It>
239struct pointer_traits<__wrap_iter<_It> > {
240 typedef __wrap_iter<_It> pointer;
241 typedef typename pointer_traits<_It>::element_type element_type;
242 typedef typename pointer_traits<_It>::difference_type difference_type;
243
244 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR static element_type* to_address(pointer __w) _NOEXCEPT {
245 return std::__to_address(__w.base());
246 }
247};
248
249_LIBCPP_END_NAMESPACE_STD
250
251#endif // _LIBCPP___ITERATOR_WRAP_ITER_H