1// Copyright (C) 2016 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#ifndef QITERATOR_H
5#define QITERATOR_H
6
7#include <QtCore/qglobal.h>
8#include <QtCore/qcontainertools_impl.h>
9
10QT_BEGIN_NAMESPACE
11
12#if !defined(QT_NO_JAVA_STYLE_ITERATORS)
13
14#ifdef Q_QDOC
15#define Q_DISABLE_BACKWARD_ITERATOR
16#else
17#define Q_DISABLE_BACKWARD_ITERATOR \
18 template<typename It = decltype(i), QtPrivate::IfIteratorCanMoveBackwards<It> = true>
19#endif
20
21#define Q_DECLARE_SEQUENTIAL_ITERATOR(C) \
22\
23template <class T> \
24class Q##C##Iterator \
25{ \
26 typedef typename Q##C<T>::const_iterator const_iterator; \
27 Q##C<T> c; \
28 const_iterator i; \
29public: \
30 inline Q##C##Iterator(const Q##C<T> &container) \
31 : c(container), i(c.constBegin()) {} \
32 inline Q##C##Iterator &operator=(const Q##C<T> &container) \
33 { c = container; i = c.constBegin(); return *this; } \
34 inline void toFront() { i = c.constBegin(); } \
35 inline void toBack() { i = c.constEnd(); } \
36 inline bool hasNext() const { return i != c.constEnd(); } \
37 inline const T &next() { return *i++; } \
38 inline const T &peekNext() const { return *i; } \
39 Q_DISABLE_BACKWARD_ITERATOR \
40 inline bool hasPrevious() const { return i != c.constBegin(); } \
41 Q_DISABLE_BACKWARD_ITERATOR \
42 inline const T &previous() { return *--i; } \
43 Q_DISABLE_BACKWARD_ITERATOR \
44 inline const T &peekPrevious() const { const_iterator p = i; return *--p; } \
45 inline bool findNext(const T &t) \
46 { while (i != c.constEnd()) if (*i++ == t) return true; return false; } \
47 Q_DISABLE_BACKWARD_ITERATOR \
48 inline bool findPrevious(const T &t) \
49 { while (i != c.constBegin()) if (*(--i) == t) return true; \
50 return false; } \
51};
52
53#define Q_DECLARE_MUTABLE_SEQUENTIAL_ITERATOR(C) \
54\
55template <class T> \
56class QMutable##C##Iterator \
57{ \
58 typedef typename Q##C<T>::iterator iterator; \
59 typedef typename Q##C<T>::const_iterator const_iterator; \
60 Q##C<T> *c; \
61 iterator i, n; \
62 inline bool item_exists() const { return const_iterator(n) != c->constEnd(); } \
63public: \
64 inline QMutable##C##Iterator(Q##C<T> &container) \
65 : c(&container) \
66 { i = c->begin(); n = c->end(); } \
67 inline QMutable##C##Iterator &operator=(Q##C<T> &container) \
68 { c = &container; i = c->begin(); n = c->end(); return *this; } \
69 inline void toFront() { i = c->begin(); n = c->end(); } \
70 inline void toBack() { i = c->end(); n = i; } \
71 inline bool hasNext() const { return c->constEnd() != const_iterator(i); } \
72 inline T &next() { n = i++; return *n; } \
73 inline T &peekNext() const { return *i; } \
74 Q_DISABLE_BACKWARD_ITERATOR \
75 inline bool hasPrevious() const { return c->constBegin() != const_iterator(i); } \
76 Q_DISABLE_BACKWARD_ITERATOR \
77 inline T &previous() { n = --i; return *n; } \
78 Q_DISABLE_BACKWARD_ITERATOR \
79 inline T &peekPrevious() const { iterator p = i; return *--p; } \
80 inline void remove() \
81 { if (c->constEnd() != const_iterator(n)) { i = c->erase(n); n = c->end(); } } \
82 inline void setValue(const T &t) const { if (c->constEnd() != const_iterator(n)) *n = t; } \
83 inline T &value() { Q_ASSERT(item_exists()); return *n; } \
84 inline const T &value() const { Q_ASSERT(item_exists()); return *n; } \
85 inline void insert(const T &t) { n = i = c->insert(i, t); ++i; } \
86 inline bool findNext(const T &t) \
87 { while (c->constEnd() != const_iterator(n = i)) if (*i++ == t) return true; return false; } \
88 Q_DISABLE_BACKWARD_ITERATOR \
89 inline bool findPrevious(const T &t) \
90 { while (c->constBegin() != const_iterator(i)) if (*(n = --i) == t) return true; \
91 n = c->end(); return false; } \
92};
93
94#define Q_DECLARE_ASSOCIATIVE_ITERATOR(C) \
95\
96template <class Key, class T> \
97class Q##C##Iterator \
98{ \
99 typedef typename Q##C<Key,T>::const_iterator const_iterator; \
100 Q##C<Key,T> c; \
101 const_iterator i, n; \
102 inline bool item_exists() const { return n != c.constEnd(); } \
103public: \
104 typedef const_iterator Item; \
105 inline Q##C##Iterator(const Q##C<Key,T> &container) \
106 : c(container), i(c.constBegin()), n(c.constEnd()) {} \
107 inline Q##C##Iterator &operator=(const Q##C<Key,T> &container) \
108 { c = container; i = c.constBegin(); n = c.constEnd(); return *this; } \
109 inline void toFront() { i = c.constBegin(); n = c.constEnd(); } \
110 inline void toBack() { i = c.constEnd(); n = c.constEnd(); } \
111 inline bool hasNext() const { return i != c.constEnd(); } \
112 inline Item next() { n = i++; return n; } \
113 inline Item peekNext() const { return i; } \
114 Q_DISABLE_BACKWARD_ITERATOR \
115 inline bool hasPrevious() const { return i != c.constBegin(); } \
116 Q_DISABLE_BACKWARD_ITERATOR \
117 inline Item previous() { n = --i; return n; } \
118 Q_DISABLE_BACKWARD_ITERATOR \
119 inline Item peekPrevious() const { const_iterator p = i; return --p; } \
120 inline const T &value() const { Q_ASSERT(item_exists()); return *n; } \
121 inline const Key &key() const { Q_ASSERT(item_exists()); return n.key(); } \
122 inline bool findNext(const T &t) \
123 { while ((n = i) != c.constEnd()) if (*i++ == t) return true; return false; } \
124 Q_DISABLE_BACKWARD_ITERATOR \
125 inline bool findPrevious(const T &t) \
126 { while (i != c.constBegin()) if (*(n = --i) == t) return true; \
127 n = c.constEnd(); return false; } \
128};
129
130#define Q_DECLARE_MUTABLE_ASSOCIATIVE_ITERATOR(C) \
131\
132template <class Key, class T> \
133class QMutable##C##Iterator \
134{ \
135 typedef typename Q##C<Key,T>::iterator iterator; \
136 typedef typename Q##C<Key,T>::const_iterator const_iterator; \
137 Q##C<Key,T> *c; \
138 iterator i, n; \
139 inline bool item_exists() const { return const_iterator(n) != c->constEnd(); } \
140public: \
141 typedef iterator Item; \
142 inline QMutable##C##Iterator(Q##C<Key,T> &container) \
143 : c(&container) \
144 { i = c->begin(); n = c->end(); } \
145 inline QMutable##C##Iterator &operator=(Q##C<Key,T> &container) \
146 { c = &container; i = c->begin(); n = c->end(); return *this; } \
147 inline void toFront() { i = c->begin(); n = c->end(); } \
148 inline void toBack() { i = c->end(); n = c->end(); } \
149 inline bool hasNext() const { return const_iterator(i) != c->constEnd(); } \
150 inline Item next() { n = i++; return n; } \
151 inline Item peekNext() const { return i; } \
152 Q_DISABLE_BACKWARD_ITERATOR \
153 inline bool hasPrevious() const { return const_iterator(i) != c->constBegin(); } \
154 Q_DISABLE_BACKWARD_ITERATOR \
155 inline Item previous() { n = --i; return n; } \
156 Q_DISABLE_BACKWARD_ITERATOR \
157 inline Item peekPrevious() const { iterator p = i; return --p; } \
158 inline void remove() \
159 { if (const_iterator(n) != c->constEnd()) { i = c->erase(n); n = c->end(); } } \
160 inline void setValue(const T &t) { if (const_iterator(n) != c->constEnd()) *n = t; } \
161 inline T &value() { Q_ASSERT(item_exists()); return *n; } \
162 inline const T &value() const { Q_ASSERT(item_exists()); return *n; } \
163 inline const Key &key() const { Q_ASSERT(item_exists()); return n.key(); } \
164 inline bool findNext(const T &t) \
165 { while (const_iterator(n = i) != c->constEnd()) if (*i++ == t) return true; return false; } \
166 Q_DISABLE_BACKWARD_ITERATOR \
167 inline bool findPrevious(const T &t) \
168 { while (const_iterator(i) != c->constBegin()) if (*(n = --i) == t) return true; \
169 n = c->end(); return false; } \
170};
171
172#define Q_DECLARE_ASSOCIATIVE_FORWARD_ITERATOR(C) \
173\
174template <class Key, class T> \
175class Q##C##Iterator \
176{ \
177 typedef typename Q##C<Key,T>::const_iterator const_iterator; \
178 Q##C<Key,T> c; \
179 const_iterator i, n; \
180 inline bool item_exists() const { return n != c.constEnd(); } \
181public: \
182 typedef const_iterator Item; \
183 inline Q##C##Iterator(const Q##C<Key,T> &container) \
184 : c(container), i(c.constBegin()), n(c.constEnd()) {} \
185 inline Q##C##Iterator &operator=(const Q##C<Key,T> &container) \
186 { c = container; i = c.constBegin(); n = c.constEnd(); return *this; } \
187 inline void toFront() { i = c.constBegin(); n = c.constEnd(); } \
188 inline void toBack() { i = c.constEnd(); n = c.constEnd(); } \
189 inline bool hasNext() const { return i != c.constEnd(); } \
190 inline Item next() { n = i++; return n; } \
191 inline Item peekNext() const { return i; } \
192 inline const T &value() const { Q_ASSERT(item_exists()); return *n; } \
193 inline const Key &key() const { Q_ASSERT(item_exists()); return n.key(); } \
194 inline bool findNext(const T &t) \
195 { while ((n = i) != c.constEnd()) if (*i++ == t) return true; return false; } \
196};
197
198#define Q_DECLARE_MUTABLE_ASSOCIATIVE_FORWARD_ITERATOR(C) \
199\
200template <class Key, class T> \
201class QMutable##C##Iterator \
202{ \
203 typedef typename Q##C<Key,T>::iterator iterator; \
204 typedef typename Q##C<Key,T>::const_iterator const_iterator; \
205 Q##C<Key,T> *c; \
206 iterator i, n; \
207 inline bool item_exists() const { return const_iterator(n) != c->constEnd(); } \
208public: \
209 typedef iterator Item; \
210 inline QMutable##C##Iterator(Q##C<Key,T> &container) \
211 : c(&container) \
212 { i = c->begin(); n = c->end(); } \
213 inline QMutable##C##Iterator &operator=(Q##C<Key,T> &container) \
214 { c = &container; i = c->begin(); n = c->end(); return *this; } \
215 inline void toFront() { i = c->begin(); n = c->end(); } \
216 inline void toBack() { i = c->end(); n = c->end(); } \
217 inline bool hasNext() const { return const_iterator(i) != c->constEnd(); } \
218 inline Item next() { n = i++; return n; } \
219 inline Item peekNext() const { return i; } \
220 inline void remove() \
221 { if (const_iterator(n) != c->constEnd()) { i = c->erase(n); n = c->end(); } } \
222 inline void setValue(const T &t) { if (const_iterator(n) != c->constEnd()) *n = t; } \
223 inline T &value() { Q_ASSERT(item_exists()); return *n; } \
224 inline const T &value() const { Q_ASSERT(item_exists()); return *n; } \
225 inline const Key &key() const { Q_ASSERT(item_exists()); return n.key(); } \
226 inline bool findNext(const T &t) \
227 { while (const_iterator(n = i) != c->constEnd()) if (*i++ == t) return true; return false; } \
228};
229
230
231#else // QT_NO_JAVA_STYLE_ITERATORS
232#define Q_DECLARE_SEQUENTIAL_ITERATOR(C)
233#define Q_DECLARE_MUTABLE_SEQUENTIAL_ITERATOR(C)
234#define Q_DECLARE_ASSOCIATIVE_ITERATOR(C)
235#define Q_DECLARE_MUTABLE_ASSOCIATIVE_ITERATOR(C)
236#define Q_DECLARE_ASSOCIATIVE_FORWARD_ITERATOR(C)
237#define Q_DECLARE_MUTABLE_ASSOCIATIVE_FORWARD_ITERATOR(C)
238#endif // QT_NO_JAVA_STYLE_ITERATORS
239
240template<typename Key, typename T, class Iterator>
241class QKeyValueIterator
242{
243public:
244 typedef typename Iterator::iterator_category iterator_category;
245 typedef typename Iterator::difference_type difference_type;
246 typedef std::pair<Key, T> value_type;
247 typedef const value_type &reference;
248
249 QKeyValueIterator() = default;
250 constexpr explicit QKeyValueIterator(Iterator o) noexcept(std::is_nothrow_move_constructible<Iterator>::value)
251 : i(std::move(o)) {}
252
253 std::pair<Key, T> operator*() const {
254 return std::pair<Key, T>(i.key(), i.value());
255 }
256
257 using pointer = QtPrivate::ArrowProxy<value_type>;
258
259 pointer operator->() const {
260 return pointer{std::pair<Key, T>(i.key(), i.value())};
261 }
262
263 friend bool operator==(QKeyValueIterator lhs, QKeyValueIterator rhs) noexcept { return lhs.i == rhs.i; }
264 friend bool operator!=(QKeyValueIterator lhs, QKeyValueIterator rhs) noexcept { return lhs.i != rhs.i; }
265
266 inline QKeyValueIterator &operator++() { ++i; return *this; }
267 inline QKeyValueIterator operator++(int) { return QKeyValueIterator(i++);}
268 inline QKeyValueIterator &operator--() { --i; return *this; }
269 inline QKeyValueIterator operator--(int) { return QKeyValueIterator(i--); }
270 Iterator base() const { return i; }
271
272private:
273 Iterator i;
274};
275
276namespace QtPrivate {
277
278template <typename Map>
279class QKeyValueRangeStorage
280{
281protected:
282 Map m_map;
283public:
284 explicit QKeyValueRangeStorage(const Map &map) : m_map(map) {}
285 explicit QKeyValueRangeStorage(Map &&map) : m_map(std::move(map)) {}
286};
287
288template <typename Map>
289class QKeyValueRangeStorage<Map &>
290{
291protected:
292 Map &m_map;
293public:
294 explicit QKeyValueRangeStorage(Map &map) : m_map(map) {}
295};
296
297template <typename Map>
298class QKeyValueRange : public QKeyValueRangeStorage<Map>
299{
300public:
301 using QKeyValueRangeStorage<Map>::QKeyValueRangeStorage;
302 auto begin() { return this->m_map.keyValueBegin(); }
303 auto begin() const { return this->m_map.keyValueBegin(); }
304 auto end() { return this->m_map.keyValueEnd(); }
305 auto end() const { return this->m_map.keyValueEnd(); }
306};
307
308template <typename Map>
309QKeyValueRange(Map &) -> QKeyValueRange<Map &>;
310
311template <typename Map, std::enable_if_t<!std::is_reference_v<Map>, bool> = false>
312QKeyValueRange(Map &&) -> QKeyValueRange<std::remove_const_t<Map>>;
313
314} // namespace QtPrivate
315
316
317QT_END_NAMESPACE
318
319#endif // QITERATOR_H
320

source code of qtbase/src/corelib/tools/qiterator.h