1/****************************************************************************
2**
3** Copyright (C) 2016 The Qt Company Ltd.
4** Contact: https://www.qt.io/licensing/
5**
6** This file is part of the QtCore module of the Qt Toolkit.
7**
8** $QT_BEGIN_LICENSE:LGPL$
9** Commercial License Usage
10** Licensees holding valid commercial Qt licenses may use this file in
11** accordance with the commercial license agreement provided with the
12** Software or, alternatively, in accordance with the terms contained in
13** a written agreement between you and The Qt Company. For licensing terms
14** and conditions see https://www.qt.io/terms-conditions. For further
15** information use the contact form at https://www.qt.io/contact-us.
16**
17** GNU Lesser General Public License Usage
18** Alternatively, this file may be used under the terms of the GNU Lesser
19** General Public License version 3 as published by the Free Software
20** Foundation and appearing in the file LICENSE.LGPL3 included in the
21** packaging of this file. Please review the following information to
22** ensure the GNU Lesser General Public License version 3 requirements
23** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
24**
25** GNU General Public License Usage
26** Alternatively, this file may be used under the terms of the GNU
27** General Public License version 2.0 or (at your option) the GNU General
28** Public license version 3 or any later version approved by the KDE Free
29** Qt Foundation. The licenses are as published by the Free Software
30** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
31** included in the packaging of this file. Please review the following
32** information to ensure the GNU General Public License requirements will
33** be met: https://www.gnu.org/licenses/gpl-2.0.html and
34** https://www.gnu.org/licenses/gpl-3.0.html.
35**
36** $QT_END_LICENSE$
37**
38****************************************************************************/
39
40#ifndef QSET_H
41#define QSET_H
42
43#include <QtCore/qhash.h>
44#include <QtCore/qcontainertools_impl.h>
45
46#include <initializer_list>
47#include <iterator>
48
49QT_BEGIN_NAMESPACE
50
51
52template <class T>
53class QSet
54{
55 typedef QHash<T, QHashDummyValue> Hash;
56
57public:
58 inline QSet() noexcept {}
59 inline QSet(std::initializer_list<T> list)
60 : QSet(list.begin(), list.end()) {}
61 template <typename InputIterator, QtPrivate::IfIsInputIterator<InputIterator> = true>
62 inline QSet(InputIterator first, InputIterator last)
63 {
64 QtPrivate::reserveIfForwardIterator(this, first, last);
65 for (; first != last; ++first)
66 insert(*first);
67 }
68
69 // compiler-generated copy/move ctor/assignment operators are fine!
70 // compiler-generated destructor is fine!
71
72 inline void swap(QSet<T> &other) noexcept { q_hash.swap(other.q_hash); }
73
74 template <typename U = T>
75 QTypeTraits::compare_eq_result<U> operator==(const QSet<T> &other) const
76 { return q_hash == other.q_hash; }
77 template <typename U = T>
78 QTypeTraits::compare_eq_result<U> operator!=(const QSet<T> &other) const
79 { return q_hash != other.q_hash; }
80
81 inline qsizetype size() const { return q_hash.size(); }
82
83 inline bool isEmpty() const { return q_hash.isEmpty(); }
84
85 inline qsizetype capacity() const { return q_hash.capacity(); }
86 inline void reserve(qsizetype size);
87 inline void squeeze() { q_hash.squeeze(); }
88
89 inline void detach() { q_hash.detach(); }
90 inline bool isDetached() const { return q_hash.isDetached(); }
91
92 inline void clear() { q_hash.clear(); }
93
94 inline bool remove(const T &value) { return q_hash.remove(value) != 0; }
95
96 inline bool contains(const T &value) const { return q_hash.contains(value); }
97
98 bool contains(const QSet<T> &set) const;
99
100 class const_iterator;
101
102 class iterator
103 {
104 typedef QHash<T, QHashDummyValue> Hash;
105 typename Hash::iterator i;
106 friend class const_iterator;
107 friend class QSet<T>;
108
109 public:
110 typedef std::forward_iterator_tag iterator_category;
111 typedef qptrdiff difference_type;
112 typedef T value_type;
113 typedef const T *pointer;
114 typedef const T &reference;
115
116 inline iterator() {}
117 inline iterator(typename Hash::iterator o) : i(o) {}
118 inline iterator(const iterator &o) : i(o.i) {}
119 inline iterator &operator=(const iterator &o) { i = o.i; return *this; }
120 inline const T &operator*() const { return i.key(); }
121 inline const T *operator->() const { return &i.key(); }
122 inline bool operator==(const iterator &o) const { return i == o.i; }
123 inline bool operator!=(const iterator &o) const { return i != o.i; }
124 inline bool operator==(const const_iterator &o) const
125 { return i == o.i; }
126 inline bool operator!=(const const_iterator &o) const
127 { return i != o.i; }
128 inline iterator &operator++() { ++i; return *this; }
129 inline iterator operator++(int) { iterator r = *this; ++i; return r; }
130 };
131
132 class const_iterator
133 {
134 typedef QHash<T, QHashDummyValue> Hash;
135 typename Hash::const_iterator i;
136 friend class iterator;
137 friend class QSet<T>;
138
139 public:
140 typedef std::forward_iterator_tag iterator_category;
141 typedef qptrdiff difference_type;
142 typedef T value_type;
143 typedef const T *pointer;
144 typedef const T &reference;
145
146 inline const_iterator() {}
147 inline const_iterator(typename Hash::const_iterator o) : i(o) {}
148 inline const_iterator(const const_iterator &o) : i(o.i) {}
149 inline const_iterator(const iterator &o)
150 : i(o.i) {}
151 inline const_iterator &operator=(const const_iterator &o) { i = o.i; return *this; }
152 inline const T &operator*() const { return i.key(); }
153 inline const T *operator->() const { return &i.key(); }
154 inline bool operator==(const const_iterator &o) const { return i == o.i; }
155 inline bool operator!=(const const_iterator &o) const { return i != o.i; }
156 inline const_iterator &operator++() { ++i; return *this; }
157 inline const_iterator operator++(int) { const_iterator r = *this; ++i; return r; }
158 };
159
160 // STL style
161 inline iterator begin() { return q_hash.begin(); }
162 inline const_iterator begin() const noexcept { return q_hash.begin(); }
163 inline const_iterator cbegin() const noexcept { return q_hash.begin(); }
164 inline const_iterator constBegin() const noexcept { return q_hash.constBegin(); }
165 inline iterator end() { return q_hash.end(); }
166 inline const_iterator end() const noexcept { return q_hash.end(); }
167 inline const_iterator cend() const noexcept { return q_hash.end(); }
168 inline const_iterator constEnd() const noexcept { return q_hash.constEnd(); }
169
170 iterator erase(const_iterator i)
171 {
172 Q_ASSERT(i != constEnd());
173 return q_hash.erase(i.i);
174 }
175
176 // more Qt
177 typedef iterator Iterator;
178 typedef const_iterator ConstIterator;
179 inline qsizetype count() const { return q_hash.count(); }
180 inline iterator insert(const T &value)
181 { return static_cast<typename Hash::iterator>(q_hash.insert(value, QHashDummyValue())); }
182 iterator find(const T &value) { return q_hash.find(value); }
183 const_iterator find(const T &value) const { return q_hash.find(value); }
184 inline const_iterator constFind(const T &value) const { return find(value); }
185 QSet<T> &unite(const QSet<T> &other);
186 QSet<T> &intersect(const QSet<T> &other);
187 bool intersects(const QSet<T> &other) const;
188 QSet<T> &subtract(const QSet<T> &other);
189
190 // STL compatibility
191 typedef T key_type;
192 typedef T value_type;
193 typedef value_type *pointer;
194 typedef const value_type *const_pointer;
195 typedef value_type &reference;
196 typedef const value_type &const_reference;
197 typedef qptrdiff difference_type;
198 typedef qsizetype size_type;
199
200 inline bool empty() const { return isEmpty(); }
201 // comfort
202 inline QSet<T> &operator<<(const T &value) { insert(value); return *this; }
203 inline QSet<T> &operator|=(const QSet<T> &other) { unite(other); return *this; }
204 inline QSet<T> &operator|=(const T &value) { insert(value); return *this; }
205 inline QSet<T> &operator&=(const QSet<T> &other) { intersect(other); return *this; }
206 inline QSet<T> &operator&=(const T &value)
207 { QSet<T> result; if (contains(value)) result.insert(value); return (*this = result); }
208 inline QSet<T> &operator+=(const QSet<T> &other) { unite(other); return *this; }
209 inline QSet<T> &operator+=(const T &value) { insert(value); return *this; }
210 inline QSet<T> &operator-=(const QSet<T> &other) { subtract(other); return *this; }
211 inline QSet<T> &operator-=(const T &value) { remove(value); return *this; }
212 inline QSet<T> operator|(const QSet<T> &other) const
213 { QSet<T> result = *this; result |= other; return result; }
214 inline QSet<T> operator&(const QSet<T> &other) const
215 { QSet<T> result = *this; result &= other; return result; }
216 inline QSet<T> operator+(const QSet<T> &other) const
217 { QSet<T> result = *this; result += other; return result; }
218 inline QSet<T> operator-(const QSet<T> &other) const
219 { QSet<T> result = *this; result -= other; return result; }
220
221 QList<T> values() const;
222
223private:
224 Hash q_hash;
225};
226
227#if defined(__cpp_deduction_guides) && __cpp_deduction_guides >= 201606
228template <typename InputIterator,
229 typename ValueType = typename std::iterator_traits<InputIterator>::value_type,
230 QtPrivate::IfIsInputIterator<InputIterator> = true>
231QSet(InputIterator, InputIterator) -> QSet<ValueType>;
232#endif
233
234template <typename T>
235size_t qHash(const QSet<T> &key, size_t seed = 0)
236noexcept(noexcept(qHashRangeCommutative(key.begin(), key.end(), seed)))
237{
238 return qHashRangeCommutative(key.begin(), key.end(), seed);
239}
240
241// inline function implementations
242
243template <class T>
244Q_INLINE_TEMPLATE void QSet<T>::reserve(qsizetype asize) { q_hash.reserve(asize); }
245
246template <class T>
247Q_INLINE_TEMPLATE QSet<T> &QSet<T>::unite(const QSet<T> &other)
248{
249 if (!q_hash.isSharedWith(other.q_hash)) {
250 for (const T &e : other)
251 insert(e);
252 }
253 return *this;
254}
255
256template <class T>
257Q_INLINE_TEMPLATE QSet<T> &QSet<T>::intersect(const QSet<T> &other)
258{
259 QSet<T> copy1;
260 QSet<T> copy2;
261 if (size() <= other.size()) {
262 copy1 = *this;
263 copy2 = other;
264 } else {
265 copy1 = other;
266 copy2 = *this;
267 *this = copy1;
268 }
269 for (const auto &e : qAsConst(copy1)) {
270 if (!copy2.contains(e))
271 remove(e);
272 }
273 return *this;
274}
275
276template <class T>
277Q_INLINE_TEMPLATE bool QSet<T>::intersects(const QSet<T> &other) const
278{
279 const bool otherIsBigger = other.size() > size();
280 const QSet &smallestSet = otherIsBigger ? *this : other;
281 const QSet &biggestSet = otherIsBigger ? other : *this;
282 typename QSet::const_iterator i = smallestSet.cbegin();
283 typename QSet::const_iterator e = smallestSet.cend();
284
285 while (i != e) {
286 if (biggestSet.contains(*i))
287 return true;
288 ++i;
289 }
290
291 return false;
292}
293
294template <class T>
295Q_INLINE_TEMPLATE QSet<T> &QSet<T>::subtract(const QSet<T> &other)
296{
297 if (q_hash.isSharedWith(other.q_hash)) {
298 clear();
299 } else {
300 for (const auto &e : other)
301 remove(e);
302 }
303 return *this;
304}
305
306template <class T>
307Q_INLINE_TEMPLATE bool QSet<T>::contains(const QSet<T> &other) const
308{
309 typename QSet<T>::const_iterator i = other.constBegin();
310 while (i != other.constEnd()) {
311 if (!contains(*i))
312 return false;
313 ++i;
314 }
315 return true;
316}
317
318template <typename T>
319Q_OUTOFLINE_TEMPLATE QList<T> QSet<T>::values() const
320{
321 QList<T> result;
322 result.reserve(size());
323 typename QSet<T>::const_iterator i = constBegin();
324 while (i != constEnd()) {
325 result.append(*i);
326 ++i;
327 }
328 return result;
329}
330
331Q_DECLARE_SEQUENTIAL_ITERATOR(Set)
332
333#if !defined(QT_NO_JAVA_STYLE_ITERATORS)
334template <typename T>
335class QMutableSetIterator
336{
337 typedef typename QSet<T>::iterator iterator;
338 QSet<T> *c;
339 iterator i, n;
340 inline bool item_exists() const { return c->constEnd() != n; }
341
342public:
343 inline QMutableSetIterator(QSet<T> &container)
344 : c(&container)
345 { i = c->begin(); n = c->end(); }
346 inline QMutableSetIterator &operator=(QSet<T> &container)
347 { c = &container; i = c->begin(); n = c->end(); return *this; }
348 inline void toFront() { i = c->begin(); n = c->end(); }
349 inline void toBack() { i = c->end(); n = i; }
350 inline bool hasNext() const { return c->constEnd() != i; }
351 inline const T &next() { n = i++; return *n; }
352 inline const T &peekNext() const { return *i; }
353 inline void remove()
354 { if (c->constEnd() != n) { i = c->erase(n); n = c->end(); } }
355 inline const T &value() const { Q_ASSERT(item_exists()); return *n; }
356 inline bool findNext(const T &t)
357 { while (c->constEnd() != (n = i)) if (*i++ == t) return true; return false; }
358};
359#endif // QT_NO_JAVA_STYLE_ITERATORS
360
361QT_END_NAMESPACE
362
363#endif // QSET_H
364