1 | // Copyright (C) 2022 The Qt Company Ltd. |
---|---|
2 | // Copyright (C) 2021 Intel Corporation. |
3 | // Copyright (C) 2015 Olivier Goffart <ogoffart@woboq.com> |
4 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
5 | |
6 | #include "qvariant_p.h" |
7 | #include "qbitarray.h" |
8 | #include "qbytearray.h" |
9 | #include "qdatastream.h" |
10 | #include "qdebug.h" |
11 | #include "qmap.h" |
12 | #include "qhash.h" |
13 | #include "qdatetime.h" |
14 | #if QT_CONFIG(easingcurve) |
15 | #include "qeasingcurve.h" |
16 | #endif |
17 | #include "qlist.h" |
18 | #if QT_CONFIG(regularexpression) |
19 | #include "qregularexpression.h" |
20 | #endif |
21 | #include "qstring.h" |
22 | #include "qstringlist.h" |
23 | #include "qurl.h" |
24 | #include "qlocale.h" |
25 | #include "quuid.h" |
26 | #if QT_CONFIG(itemmodel) |
27 | #include "qabstractitemmodel.h" |
28 | #endif |
29 | #ifndef QT_BOOTSTRAPPED |
30 | #include "qcborarray.h" |
31 | #include "qcborcommon.h" |
32 | #include "qcbormap.h" |
33 | #include "qjsonvalue.h" |
34 | #include "qjsonobject.h" |
35 | #include "qjsonarray.h" |
36 | #include "qjsondocument.h" |
37 | #include "qbytearraylist.h" |
38 | #endif |
39 | #include "private/qlocale_p.h" |
40 | #include "qmetatype_p.h" |
41 | #include <qmetaobject.h> |
42 | |
43 | #ifndef QT_NO_GEOM_VARIANT |
44 | #include "qsize.h" |
45 | #include "qpoint.h" |
46 | #include "qrect.h" |
47 | #include "qline.h" |
48 | #endif |
49 | |
50 | #include <memory> |
51 | |
52 | #include <cmath> |
53 | #include <float.h> |
54 | #include <cstring> |
55 | |
56 | QT_BEGIN_NAMESPACE |
57 | |
58 | using namespace Qt::StringLiterals; |
59 | |
60 | namespace { // anonymous used to hide QVariant handlers |
61 | |
62 | static qlonglong qMetaTypeNumberBySize(const QVariant::Private *d) |
63 | { |
64 | switch (d->typeInterface()->size) { |
65 | case 1: |
66 | return d->get<signed char>(); |
67 | case 2: |
68 | return d->get<short>(); |
69 | case 4: |
70 | return d->get<int>(); |
71 | case 8: |
72 | return d->get<qlonglong>(); |
73 | } |
74 | Q_UNREACHABLE_RETURN(0); |
75 | } |
76 | |
77 | static qlonglong qMetaTypeNumber(const QVariant::Private *d) |
78 | { |
79 | switch (d->typeInterface()->typeId) { |
80 | case QMetaType::Int: |
81 | case QMetaType::LongLong: |
82 | case QMetaType::Char: |
83 | case QMetaType::SChar: |
84 | case QMetaType::Short: |
85 | case QMetaType::Long: |
86 | return qMetaTypeNumberBySize(d); |
87 | case QMetaType::Float: |
88 | return qRound64(f: d->get<float>()); |
89 | case QMetaType::Double: |
90 | return qRound64(d: d->get<double>()); |
91 | #ifndef QT_BOOTSTRAPPED |
92 | case QMetaType::QJsonValue: |
93 | return d->get<QJsonValue>().toDouble(); |
94 | case QMetaType::QCborValue: |
95 | return d->get<QCborValue>().toInteger(); |
96 | #endif |
97 | } |
98 | Q_UNREACHABLE_RETURN(0); |
99 | } |
100 | |
101 | static qulonglong qMetaTypeUNumber(const QVariant::Private *d) |
102 | { |
103 | switch (d->typeInterface()->size) { |
104 | case 1: |
105 | return d->get<unsigned char>(); |
106 | case 2: |
107 | return d->get<unsigned short>(); |
108 | case 4: |
109 | return d->get<unsigned int>(); |
110 | case 8: |
111 | return d->get<qulonglong>(); |
112 | } |
113 | Q_UNREACHABLE_RETURN(0); |
114 | } |
115 | |
116 | static std::optional<qlonglong> qConvertToNumber(const QVariant::Private *d, bool allowStringToBool = false) |
117 | { |
118 | bool ok; |
119 | switch (d->typeInterface()->typeId) { |
120 | case QMetaType::QString: { |
121 | const QString &s = d->get<QString>(); |
122 | if (qlonglong l = s.toLongLong(ok: &ok); ok) |
123 | return l; |
124 | if (allowStringToBool) { |
125 | if (s == "false"_L1|| s == "0"_L1) |
126 | return 0; |
127 | if (s == "true"_L1|| s == "1"_L1) |
128 | return 1; |
129 | } |
130 | return std::nullopt; |
131 | } |
132 | case QMetaType::QChar: |
133 | return d->get<QChar>().unicode(); |
134 | case QMetaType::QByteArray: |
135 | if (qlonglong l = d->get<QByteArray>().toLongLong(ok: &ok); ok) |
136 | return l; |
137 | return std::nullopt; |
138 | case QMetaType::Bool: |
139 | return qlonglong(d->get<bool>()); |
140 | #ifndef QT_BOOTSTRAPPED |
141 | case QMetaType::QCborValue: |
142 | if (!d->get<QCborValue>().isInteger() && !d->get<QCborValue>().isDouble()) |
143 | break; |
144 | return qMetaTypeNumber(d); |
145 | case QMetaType::QJsonValue: |
146 | if (!d->get<QJsonValue>().isDouble()) |
147 | break; |
148 | Q_FALLTHROUGH(); |
149 | #endif |
150 | case QMetaType::Double: |
151 | case QMetaType::Int: |
152 | case QMetaType::Char: |
153 | case QMetaType::SChar: |
154 | case QMetaType::Short: |
155 | case QMetaType::Long: |
156 | case QMetaType::Float: |
157 | case QMetaType::LongLong: |
158 | return qMetaTypeNumber(d); |
159 | case QMetaType::ULongLong: |
160 | case QMetaType::UInt: |
161 | case QMetaType::UChar: |
162 | case QMetaType::Char16: |
163 | case QMetaType::Char32: |
164 | case QMetaType::UShort: |
165 | case QMetaType::ULong: |
166 | return qlonglong(qMetaTypeUNumber(d)); |
167 | } |
168 | |
169 | if (d->typeInterface()->flags & QMetaType::IsEnumeration |
170 | || d->typeInterface()->typeId == QMetaType::QCborSimpleType) |
171 | return qMetaTypeNumberBySize(d); |
172 | |
173 | return std::nullopt; |
174 | } |
175 | |
176 | static std::optional<double> qConvertToRealNumber(const QVariant::Private *d) |
177 | { |
178 | bool ok; |
179 | switch (d->typeInterface()->typeId) { |
180 | case QMetaType::QString: |
181 | if (double r = d->get<QString>().toDouble(ok: &ok); ok) |
182 | return r; |
183 | return std::nullopt; |
184 | case QMetaType::Double: |
185 | return d->get<double>(); |
186 | case QMetaType::Float: |
187 | return double(d->get<float>()); |
188 | case QMetaType::Float16: |
189 | return double(d->get<qfloat16>()); |
190 | case QMetaType::ULongLong: |
191 | case QMetaType::UInt: |
192 | case QMetaType::UChar: |
193 | case QMetaType::Char16: |
194 | case QMetaType::Char32: |
195 | case QMetaType::UShort: |
196 | case QMetaType::ULong: |
197 | return double(qMetaTypeUNumber(d)); |
198 | #ifndef QT_BOOTSTRAPPED |
199 | case QMetaType::QCborValue: |
200 | return d->get<QCborValue>().toDouble(); |
201 | case QMetaType::QJsonValue: |
202 | return d->get<QJsonValue>().toDouble(); |
203 | #endif |
204 | default: |
205 | // includes enum conversion as well as invalid types |
206 | if (std::optional<qlonglong> l = qConvertToNumber(d)) |
207 | return double(*l); |
208 | return std::nullopt; |
209 | } |
210 | } |
211 | |
212 | static bool isValidMetaTypeForVariant(const QtPrivate::QMetaTypeInterface *iface, const void *copy) |
213 | { |
214 | using namespace QtMetaTypePrivate; |
215 | if (!iface || iface->size == 0) |
216 | return false; |
217 | |
218 | Q_ASSERT(!isInterfaceFor<void>(iface)); // only void should have size 0 |
219 | if (!isCopyConstructible(iface) || !isDestructible(iface)) { |
220 | // all meta types must be copyable (because QVariant is) and |
221 | // destructible (because QVariant owns it) |
222 | qWarning(msg: "QVariant: Provided metatype for '%s' does not support destruction and " |
223 | "copy construction", iface->name); |
224 | return false; |
225 | } |
226 | if (!copy && !isDefaultConstructible(iface)) { |
227 | // non-default-constructible types are acceptable, but not if you're |
228 | // asking us to construct from nothing |
229 | qWarning(msg: "QVariant: Cannot create type '%s' without a default constructor", iface->name); |
230 | return false; |
231 | } |
232 | |
233 | return true; |
234 | } |
235 | |
236 | enum CustomConstructMoveOptions { |
237 | UseCopy, // custom construct uses the copy ctor unconditionally |
238 | // future option: TryMove: uses move ctor if available, else copy ctor |
239 | ForceMove, // custom construct use the move ctor (which must exist) |
240 | }; |
241 | |
242 | enum CustomConstructNullabilityOption { |
243 | MaybeNull, // copy might be null, might be non-null |
244 | NonNull, // copy is guarantueed to be non-null |
245 | // future option: AlwaysNull? |
246 | }; |
247 | |
248 | // the type of d has already been set, but other field are not set |
249 | template <CustomConstructMoveOptions moveOption = UseCopy, CustomConstructNullabilityOption nullability = MaybeNull> |
250 | static void customConstruct(const QtPrivate::QMetaTypeInterface *iface, QVariant::Private *d, |
251 | std::conditional_t<moveOption == ForceMove, void *, const void *> copy) |
252 | { |
253 | using namespace QtMetaTypePrivate; |
254 | Q_ASSERT(iface); |
255 | Q_ASSERT(iface->size); |
256 | Q_ASSERT(!isInterfaceFor<void>(iface)); |
257 | Q_ASSERT(isCopyConstructible(iface)); |
258 | Q_ASSERT(isDestructible(iface)); |
259 | Q_ASSERT(copy || isDefaultConstructible(iface)); |
260 | if constexpr (moveOption == ForceMove) |
261 | Q_ASSERT(isMoveConstructible(iface)); |
262 | if constexpr (nullability == NonNull) |
263 | Q_ASSERT(copy != nullptr); |
264 | |
265 | // need to check for nullptr_t here, as this can get called by fromValue(nullptr). fromValue() uses |
266 | // std::addressof(value) which in this case returns the address of the nullptr object. |
267 | // ### Qt 7: remove nullptr_t special casing |
268 | d->is_null = !copy QT6_ONLY(|| isInterfaceFor<std::nullptr_t>(iface)); |
269 | |
270 | if (QVariant::Private::canUseInternalSpace(type: iface)) { |
271 | d->is_shared = false; |
272 | if (!copy && !iface->defaultCtr) |
273 | return; // trivial default constructor and it's OK to build in 0-filled storage, which we've already done |
274 | if constexpr (moveOption == ForceMove && nullability == NonNull) |
275 | moveConstruct(iface, d->data.data, copy); |
276 | else |
277 | construct(iface, d->data.data, copy); |
278 | } else { |
279 | d->data.shared = customConstructShared(iface->size, iface->alignment, [=](void *where) { |
280 | if constexpr (moveOption == ForceMove && nullability == NonNull) |
281 | moveConstruct(iface, where, copy); |
282 | else |
283 | construct(iface, where, copy); |
284 | }); |
285 | d->is_shared = true; |
286 | } |
287 | } |
288 | |
289 | static void customClear(QVariant::Private *d) |
290 | { |
291 | const QtPrivate::QMetaTypeInterface *iface = d->typeInterface(); |
292 | if (!iface) |
293 | return; |
294 | if (!d->is_shared) { |
295 | QtMetaTypePrivate::destruct(iface, where: d->data.data); |
296 | } else { |
297 | QtMetaTypePrivate::destruct(iface, where: d->data.shared->data()); |
298 | QVariant::PrivateShared::free(p: d->data.shared); |
299 | } |
300 | } |
301 | |
302 | static QVariant::Private clonePrivate(const QVariant::Private &other) |
303 | { |
304 | QVariant::Private d = other; |
305 | if (d.is_shared) { |
306 | d.data.shared->ref.ref(); |
307 | } else if (const QtPrivate::QMetaTypeInterface *iface = d.typeInterface()) { |
308 | if (Q_LIKELY(d.canUseInternalSpace(iface))) { |
309 | // if not trivially copyable, ask to copy (if it's trivially |
310 | // copyable, we've already copied it) |
311 | if (iface->copyCtr) |
312 | QtMetaTypePrivate::copyConstruct(iface, where: d.data.data, copy: other.data.data); |
313 | } else { |
314 | // highly unlikely, but possible case: type has changed relocatability |
315 | // between builds |
316 | d.data.shared = QVariant::PrivateShared::create(size: iface->size, align: iface->alignment); |
317 | QtMetaTypePrivate::copyConstruct(iface, where: d.data.shared->data(), copy: other.data.data); |
318 | } |
319 | |
320 | } |
321 | return d; |
322 | } |
323 | |
324 | } // anonymous used to hide QVariant handlers |
325 | |
326 | /*! |
327 | \class QVariant |
328 | \inmodule QtCore |
329 | \brief The QVariant class acts like a union for the most common Qt data types. |
330 | |
331 | \ingroup objectmodel |
332 | \ingroup shared |
333 | |
334 | \compares equality |
335 | |
336 | Because C++ forbids unions from including types that have |
337 | non-default constructors or destructors, most interesting Qt |
338 | classes cannot be used in unions. Without QVariant, this would be |
339 | a problem for QObject::property() and for database work, etc. |
340 | |
341 | A QVariant object holds a single value of a single typeId() at a |
342 | time. (Some types are multi-valued, for example a string list.) |
343 | You can find out what type, T, the variant holds, convert it to a |
344 | different type using convert(), get its value using one of the |
345 | toT() functions (e.g., toSize()), and check whether the type can |
346 | be converted to a particular type using canConvert(). |
347 | |
348 | The methods named toT() (e.g., toInt(), toString()) are const. If |
349 | you ask for the stored type, they return a copy of the stored |
350 | object. If you ask for a type that can be generated from the |
351 | stored type, toT() copies and converts and leaves the object |
352 | itself unchanged. If you ask for a type that cannot be generated |
353 | from the stored type, the result depends on the type; see the |
354 | function documentation for details. |
355 | |
356 | Here is some example code to demonstrate the use of QVariant: |
357 | |
358 | \snippet code/src_corelib_kernel_qvariant.cpp 0 |
359 | |
360 | You can even store QList<QVariant> and QMap<QString, QVariant> |
361 | values in a variant, so you can easily construct arbitrarily |
362 | complex data structures of arbitrary types. This is very powerful |
363 | and versatile, but may prove less memory and speed efficient than |
364 | storing specific types in standard data structures. |
365 | |
366 | QVariant also supports the notion of null values. A variant is null |
367 | if the variant contains no initialized value, or contains a null pointer. |
368 | |
369 | \snippet code/src_corelib_kernel_qvariant.cpp 1 |
370 | |
371 | QVariant can be extended to support other types than those |
372 | mentioned in the \l QMetaType::Type enum. |
373 | See \l{Creating Custom Qt Types}{Creating Custom Qt Types} for details. |
374 | |
375 | \section1 A Note on GUI Types |
376 | |
377 | Because QVariant is part of the Qt Core module, it cannot provide |
378 | conversion functions to data types defined in Qt GUI, such as |
379 | QColor, QImage, and QPixmap. In other words, there is no \c |
380 | toColor() function. Instead, you can use the QVariant::value() or |
381 | the qvariant_cast() template function. For example: |
382 | |
383 | \snippet code/src_corelib_kernel_qvariant.cpp 2 |
384 | |
385 | The inverse conversion (e.g., from QColor to QVariant) is |
386 | automatic for all data types supported by QVariant, including |
387 | GUI-related types: |
388 | |
389 | \snippet code/src_corelib_kernel_qvariant.cpp 3 |
390 | |
391 | \section1 Using canConvert() and convert() Consecutively |
392 | |
393 | When using canConvert() and convert() consecutively, it is possible for |
394 | canConvert() to return true, but convert() to return false. This |
395 | is typically because canConvert() only reports the general ability of |
396 | QVariant to convert between types given suitable data; it is still |
397 | possible to supply data which cannot actually be converted. |
398 | |
399 | For example, \c{canConvert(QMetaType::fromType<int>())} would return true |
400 | when called on a variant containing a string because, in principle, |
401 | QVariant is able to convert strings of numbers to integers. |
402 | However, if the string contains non-numeric characters, it cannot be |
403 | converted to an integer, and any attempt to convert it will fail. |
404 | Hence, it is important to have both functions return true for a |
405 | successful conversion. |
406 | |
407 | \sa QMetaType |
408 | */ |
409 | |
410 | /*! |
411 | \deprecated Use \l QMetaType::Type instead. |
412 | \enum QVariant::Type |
413 | |
414 | This enum type defines the types of variable that a QVariant can |
415 | contain. |
416 | |
417 | \value Invalid no type |
418 | \value BitArray a QBitArray |
419 | \value Bitmap a QBitmap |
420 | \value Bool a bool |
421 | \value Brush a QBrush |
422 | \value ByteArray a QByteArray |
423 | \value Char a QChar |
424 | \value Color a QColor |
425 | \value Cursor a QCursor |
426 | \value Date a QDate |
427 | \value DateTime a QDateTime |
428 | \value Double a double |
429 | \value EasingCurve a QEasingCurve |
430 | \value Uuid a QUuid |
431 | \value ModelIndex a QModelIndex |
432 | \value [since 5.5] PersistentModelIndex a QPersistentModelIndex |
433 | \value Font a QFont |
434 | \value Hash a QVariantHash |
435 | \value Icon a QIcon |
436 | \value Image a QImage |
437 | \value Int an int |
438 | \value KeySequence a QKeySequence |
439 | \value Line a QLine |
440 | \value LineF a QLineF |
441 | \value List a QVariantList |
442 | \value Locale a QLocale |
443 | \value LongLong a \l qlonglong |
444 | \value Map a QVariantMap |
445 | \value Transform a QTransform |
446 | \value Matrix4x4 a QMatrix4x4 |
447 | \value Palette a QPalette |
448 | \value Pen a QPen |
449 | \value Pixmap a QPixmap |
450 | \value Point a QPoint |
451 | \value PointF a QPointF |
452 | \value Polygon a QPolygon |
453 | \value PolygonF a QPolygonF |
454 | \value Quaternion a QQuaternion |
455 | \value Rect a QRect |
456 | \value RectF a QRectF |
457 | \value RegularExpression a QRegularExpression |
458 | \value Region a QRegion |
459 | \value Size a QSize |
460 | \value SizeF a QSizeF |
461 | \value SizePolicy a QSizePolicy |
462 | \value String a QString |
463 | \value StringList a QStringList |
464 | \value TextFormat a QTextFormat |
465 | \value TextLength a QTextLength |
466 | \value Time a QTime |
467 | \value UInt a \l uint |
468 | \value ULongLong a \l qulonglong |
469 | \value Url a QUrl |
470 | \value Vector2D a QVector2D |
471 | \value Vector3D a QVector3D |
472 | \value Vector4D a QVector4D |
473 | |
474 | \value UserType Base value for user-defined types. |
475 | |
476 | \omitvalue LastGuiType |
477 | \omitvalue LastCoreType |
478 | \omitvalue LastType |
479 | */ |
480 | |
481 | /*! |
482 | \fn QVariant::QVariant(QVariant &&other) |
483 | |
484 | Move-constructs a QVariant instance, making it point at the same |
485 | object that \a other was pointing to. |
486 | |
487 | \since 5.2 |
488 | */ |
489 | |
490 | /*! |
491 | \fn QVariant &QVariant::operator=(QVariant &&other) |
492 | |
493 | Move-assigns \a other to this QVariant instance. |
494 | |
495 | \since 5.2 |
496 | */ |
497 | |
498 | /*! |
499 | \fn QVariant::QVariant() |
500 | |
501 | Constructs an invalid variant. |
502 | */ |
503 | |
504 | /*! |
505 | \fn QVariant::create(int type, const void *copy) |
506 | |
507 | \internal |
508 | |
509 | Constructs a variant private of type \a type, and initializes with \a copy if |
510 | \a copy is not \nullptr. |
511 | |
512 | */ |
513 | //### Qt 7: Remove in favor of QMetaType overload |
514 | void QVariant::create(int type, const void *copy) |
515 | { |
516 | create(type: QMetaType(type), copy); |
517 | } |
518 | |
519 | /*! |
520 | \fn QVariant::create(int type, const void *copy) |
521 | |
522 | \internal |
523 | \overload |
524 | */ |
525 | void QVariant::create(QMetaType type, const void *copy) |
526 | { |
527 | *this = QVariant::fromMetaType(type, copy); |
528 | } |
529 | |
530 | /*! |
531 | \fn QVariant::~QVariant() |
532 | |
533 | Destroys the QVariant and the contained object. |
534 | */ |
535 | |
536 | QVariant::~QVariant() |
537 | { |
538 | if (!d.is_shared || !d.data.shared->ref.deref()) |
539 | customClear(d: &d); |
540 | } |
541 | |
542 | /*! |
543 | \fn QVariant::QVariant(const QVariant &p) |
544 | |
545 | Constructs a copy of the variant, \a p, passed as the argument to |
546 | this constructor. |
547 | */ |
548 | |
549 | QVariant::QVariant(const QVariant &p) |
550 | : d(clonePrivate(other: p.d)) |
551 | { |
552 | } |
553 | |
554 | /*! |
555 | \fn template <typename T, typename... Args, QVariant::if_constructible<T, Args...> = true> QVariant::QVariant(std::in_place_type_t<T>, Args&&... args) noexcept(is_noexcept_constructible<q20::remove_cvref_t<T>, Args...>::value) |
556 | |
557 | \since 6.6 |
558 | Constructs a new variant containing a value of type \c T. The contained |
559 | value is is initialized with the arguments |
560 | \c{std::forward<Args>(args)...}. |
561 | |
562 | This overload only participates in overload resolution if \c T can be |
563 | constructed from \a args. |
564 | |
565 | This constructor is provided for STL/std::any compatibility. |
566 | |
567 | \overload |
568 | */ |
569 | |
570 | /*! |
571 | |
572 | \fn template <typename T, typename U, typename... Args, QVariant::if_constructible<T, std::initializer_list<U> &, Args...> = true> explicit QVariant::QVariant(std::in_place_type_t<T>, std::initializer_list<U> il, Args&&... args) noexcept(is_noexcept_constructible<q20::remove_cvref_t<T>, std::initializer_list<U> &, Args... >::value) |
573 | |
574 | \since 6.6 |
575 | \overload |
576 | This overload exists to support types with constructors taking an |
577 | \c initializer_list. It behaves otherwise equivalent to the |
578 | non-initializer list \c{in_place_type_t} overload. |
579 | */ |
580 | |
581 | |
582 | /*! |
583 | \fn template <typename T, typename... Args, QVariant::if_constructible<T, Args...> = true> QVariant::emplace(Args&&... args) |
584 | |
585 | \since 6.6 |
586 | Replaces the object currently held in \c{*this} with an object of |
587 | type \c{T}, constructed from \a{args}\c{...}. If \c{*this} was non-null, |
588 | the previously held object is destroyed first. |
589 | If possible, this method will reuse memory allocated by the QVariant. |
590 | Returns a reference to the newly-created object. |
591 | */ |
592 | |
593 | /*! |
594 | \fn template <typename T, typename U, typename... Args, QVariant::if_constructible<T, std::initializer_list<U> &, Args...> = true> QVariant::emplace(std::initializer_list<U> list, Args&&... args) |
595 | |
596 | \since 6.6 |
597 | \overload |
598 | This overload exists to support types with constructors taking an |
599 | \c initializer_list. It behaves otherwise equivalent to the |
600 | non-initializer list overload. |
601 | */ |
602 | |
603 | QVariant::QVariant(std::in_place_t, QMetaType type) : d(type.iface()) |
604 | { |
605 | // we query the metatype instead of detecting it at compile time |
606 | // so that we can change relocatability of internal types |
607 | if (!Private::canUseInternalSpace(type: type.iface())) { |
608 | d.data.shared = PrivateShared::create(size: type.sizeOf(), align: type.alignOf()); |
609 | d.is_shared = true; |
610 | } |
611 | } |
612 | |
613 | /*! |
614 | \internal |
615 | Returns a pointer to data suitable for placement new |
616 | of an object of type \a type |
617 | Changes the variant's metatype to \a type |
618 | */ |
619 | void *QVariant::prepareForEmplace(QMetaType type) |
620 | { |
621 | /* There are two cases where we can reuse the existing storage |
622 | (1) The new type fits in QVariant's SBO storage |
623 | (2) We are using the externally allocated storage, the variant is |
624 | detached, and the new type fits into the existing storage. |
625 | In all other cases (3), we cannot reuse the storage. |
626 | */ |
627 | auto typeFits = [&] { |
628 | auto newIface = type.iface(); |
629 | auto oldIface = d.typeInterface(); |
630 | auto newSize = PrivateShared::computeAllocationSize(size: newIface->size, align: newIface->alignment); |
631 | auto oldSize = PrivateShared::computeAllocationSize(size: oldIface->size, align: oldIface->alignment); |
632 | return newSize <= oldSize; |
633 | }; |
634 | if (Private::canUseInternalSpace(type: type.iface())) { // (1) |
635 | clear(); |
636 | d.packedType = quintptr(type.iface()) >> 2; |
637 | return d.data.data; |
638 | } else if (d.is_shared && isDetached() && typeFits()) { // (2) |
639 | QtMetaTypePrivate::destruct(iface: d.typeInterface(), where: d.data.shared->data()); |
640 | // compare QVariant::PrivateShared::create |
641 | const auto ps = d.data.shared; |
642 | const auto align = type.alignOf(); |
643 | ps->offset = PrivateShared::computeOffset(ps, align); |
644 | d.packedType = quintptr(type.iface()) >> 2; |
645 | return ps->data(); |
646 | } |
647 | // (3) |
648 | QVariant newVariant(std::in_place, type); |
649 | swap(other&: newVariant); |
650 | // const cast is safe, we're in a non-const method |
651 | return const_cast<void *>(d.storage()); |
652 | } |
653 | |
654 | /*! |
655 | \fn QVariant::QVariant(const QString &val) noexcept |
656 | |
657 | Constructs a new variant with a string value, \a val. |
658 | */ |
659 | |
660 | /*! |
661 | \fn QVariant::QVariant(QLatin1StringView val) |
662 | |
663 | Constructs a new variant with a QString value from the Latin-1 |
664 | string viewed by \a val. |
665 | */ |
666 | |
667 | /*! |
668 | \fn QVariant::QVariant(const char *val) |
669 | |
670 | Constructs a new variant with a string value of \a val. |
671 | The variant creates a deep copy of \a val into a QString assuming |
672 | UTF-8 encoding on the input \a val. |
673 | |
674 | Note that \a val is converted to a QString for storing in the |
675 | variant and QVariant::userType() will return QMetaType::QString for |
676 | the variant. |
677 | |
678 | You can disable this operator by defining \c |
679 | QT_NO_CAST_FROM_ASCII when you compile your applications. |
680 | */ |
681 | |
682 | /*! |
683 | \fn QVariant::QVariant(const QStringList &val) noexcept |
684 | |
685 | Constructs a new variant with a string list value, \a val. |
686 | */ |
687 | |
688 | /*! |
689 | \fn QVariant::QVariant(const QMap<QString, QVariant> &val) noexcept |
690 | |
691 | Constructs a new variant with a map of \l {QVariant}s, \a val. |
692 | */ |
693 | |
694 | /*! |
695 | \fn QVariant::QVariant(const QHash<QString, QVariant> &val) noexcept |
696 | |
697 | Constructs a new variant with a hash of \l {QVariant}s, \a val. |
698 | */ |
699 | |
700 | /*! |
701 | \fn QVariant::QVariant(QDate val) noexcept |
702 | |
703 | Constructs a new variant with a date value, \a val. |
704 | */ |
705 | |
706 | /*! |
707 | \fn QVariant::QVariant(QTime val) noexcept |
708 | |
709 | Constructs a new variant with a time value, \a val. |
710 | */ |
711 | |
712 | /*! |
713 | \fn QVariant::QVariant(const QDateTime &val) noexcept |
714 | |
715 | Constructs a new variant with a date/time value, \a val. |
716 | */ |
717 | |
718 | /*! |
719 | \since 4.7 |
720 | \fn QVariant::QVariant(const QEasingCurve &val) |
721 | |
722 | Constructs a new variant with an easing curve value, \a val. |
723 | */ |
724 | |
725 | /*! |
726 | \since 5.0 |
727 | \fn QVariant::QVariant(QUuid val) noexcept |
728 | |
729 | Constructs a new variant with an uuid value, \a val. |
730 | */ |
731 | |
732 | /*! |
733 | \since 5.0 |
734 | \fn QVariant::QVariant(const QModelIndex &val) noexcept |
735 | |
736 | Constructs a new variant with a QModelIndex value, \a val. |
737 | */ |
738 | |
739 | /*! |
740 | \since 5.5 |
741 | \fn QVariant::QVariant(const QPersistentModelIndex &val) |
742 | |
743 | Constructs a new variant with a QPersistentModelIndex value, \a val. |
744 | */ |
745 | |
746 | /*! |
747 | \since 5.0 |
748 | \fn QVariant::QVariant(const QJsonValue &val) |
749 | |
750 | Constructs a new variant with a json value, \a val. |
751 | */ |
752 | |
753 | /*! |
754 | \since 5.0 |
755 | \fn QVariant::QVariant(const QJsonObject &val) |
756 | |
757 | Constructs a new variant with a json object value, \a val. |
758 | */ |
759 | |
760 | /*! |
761 | \since 5.0 |
762 | \fn QVariant::QVariant(const QJsonArray &val) |
763 | |
764 | Constructs a new variant with a json array value, \a val. |
765 | */ |
766 | |
767 | /*! |
768 | \since 5.0 |
769 | \fn QVariant::QVariant(const QJsonDocument &val) |
770 | |
771 | Constructs a new variant with a json document value, \a val. |
772 | */ |
773 | |
774 | /*! |
775 | \fn QVariant::QVariant(const QByteArray &val) noexcept |
776 | |
777 | Constructs a new variant with a bytearray value, \a val. |
778 | */ |
779 | |
780 | /*! |
781 | \fn QVariant::QVariant(const QBitArray &val) noexcept |
782 | |
783 | Constructs a new variant with a bitarray value, \a val. |
784 | */ |
785 | |
786 | /*! |
787 | \fn QVariant::QVariant(QPoint val) noexcept |
788 | |
789 | Constructs a new variant with a point value of \a val. |
790 | */ |
791 | |
792 | /*! |
793 | \fn QVariant::QVariant(QPointF val) noexcept |
794 | |
795 | Constructs a new variant with a point value of \a val. |
796 | */ |
797 | |
798 | /*! |
799 | \fn QVariant::QVariant(QRectF val) |
800 | |
801 | Constructs a new variant with a rect value of \a val. |
802 | */ |
803 | |
804 | /*! |
805 | \fn QVariant::QVariant(QLineF val) noexcept |
806 | |
807 | Constructs a new variant with a line value of \a val. |
808 | */ |
809 | |
810 | /*! |
811 | \fn QVariant::QVariant(QLine val) noexcept |
812 | |
813 | Constructs a new variant with a line value of \a val. |
814 | */ |
815 | |
816 | /*! |
817 | \fn QVariant::QVariant(QRect val) noexcept |
818 | |
819 | Constructs a new variant with a rect value of \a val. |
820 | */ |
821 | |
822 | /*! |
823 | \fn QVariant::QVariant(QSize val) noexcept |
824 | |
825 | Constructs a new variant with a size value of \a val. |
826 | */ |
827 | |
828 | /*! |
829 | \fn QVariant::QVariant(QSizeF val) noexcept |
830 | |
831 | Constructs a new variant with a size value of \a val. |
832 | */ |
833 | |
834 | /*! |
835 | \fn QVariant::QVariant(const QUrl &val) noexcept |
836 | |
837 | Constructs a new variant with a url value of \a val. |
838 | */ |
839 | |
840 | /*! |
841 | \fn QVariant::QVariant(int val) noexcept |
842 | |
843 | Constructs a new variant with an integer value, \a val. |
844 | */ |
845 | |
846 | /*! |
847 | \fn QVariant::QVariant(uint val) noexcept |
848 | |
849 | Constructs a new variant with an unsigned integer value, \a val. |
850 | */ |
851 | |
852 | /*! |
853 | \fn QVariant::QVariant(qlonglong val) noexcept |
854 | |
855 | Constructs a new variant with a long long integer value, \a val. |
856 | */ |
857 | |
858 | /*! |
859 | \fn QVariant::QVariant(qulonglong val) noexcept |
860 | |
861 | Constructs a new variant with an unsigned long long integer value, \a val. |
862 | */ |
863 | |
864 | |
865 | /*! |
866 | \fn QVariant::QVariant(bool val) noexcept |
867 | |
868 | Constructs a new variant with a boolean value, \a val. |
869 | */ |
870 | |
871 | /*! |
872 | \fn QVariant::QVariant(double val) noexcept |
873 | |
874 | Constructs a new variant with a floating point value, \a val. |
875 | */ |
876 | |
877 | /*! |
878 | \fn QVariant::QVariant(float val) noexcept |
879 | |
880 | Constructs a new variant with a floating point value, \a val. |
881 | \since 4.6 |
882 | */ |
883 | |
884 | /*! |
885 | \fn QVariant::QVariant(const QList<QVariant> &val) noexcept |
886 | |
887 | Constructs a new variant with a list value, \a val. |
888 | */ |
889 | |
890 | /*! |
891 | \fn QVariant::QVariant(QChar c) noexcept |
892 | |
893 | Constructs a new variant with a char value, \a c. |
894 | */ |
895 | |
896 | /*! |
897 | \fn QVariant::QVariant(const QLocale &l) noexcept |
898 | |
899 | Constructs a new variant with a locale value, \a l. |
900 | */ |
901 | |
902 | /*! |
903 | \fn QVariant::QVariant(const QRegularExpression &re) noexcept |
904 | |
905 | \since 5.0 |
906 | |
907 | Constructs a new variant with the regular expression value \a re. |
908 | */ |
909 | |
910 | /*! \fn QVariant::QVariant(Type type) |
911 | \deprecated [6.0] Use the constructor taking a QMetaType instead. |
912 | |
913 | Constructs an uninitialized variant of type \a type. This will create a |
914 | variant in a special null state that if accessed will return a default |
915 | constructed value of the \a type. |
916 | |
917 | \sa isNull() |
918 | */ |
919 | |
920 | /*! |
921 | Constructs a variant of type \a type, and initializes it with |
922 | a copy of \c{*copy} if \a copy is not \nullptr (in which case, \a copy |
923 | must point to an object of type \a type). |
924 | |
925 | Note that you have to pass the address of the object you want stored. |
926 | |
927 | Usually, you never have to use this constructor, use QVariant::fromValue() |
928 | instead to construct variants from the pointer types represented by |
929 | \c QMetaType::VoidStar, and \c QMetaType::QObjectStar. |
930 | |
931 | If \a type does not support copy construction and \a copy is not \nullptr, |
932 | the variant will be invalid. Similarly, if \a copy is \nullptr and |
933 | \a type does not support default construction, the variant will be |
934 | invalid. |
935 | |
936 | \sa QVariant::fromMetaType, QVariant::fromValue(), QMetaType::Type |
937 | */ |
938 | QVariant::QVariant(QMetaType type, const void *copy) |
939 | : d() |
940 | { |
941 | *this = fromMetaType(type, copy); |
942 | } |
943 | |
944 | QVariant::QVariant(int val) noexcept : d(std::piecewise_construct_t{}, val) {} |
945 | QVariant::QVariant(uint val) noexcept : d(std::piecewise_construct_t{}, val) {} |
946 | QVariant::QVariant(qlonglong val) noexcept : d(std::piecewise_construct_t{}, val) {} |
947 | QVariant::QVariant(qulonglong val) noexcept : d(std::piecewise_construct_t{}, val) {} |
948 | QVariant::QVariant(bool val) noexcept : d(std::piecewise_construct_t{}, val) {} |
949 | QVariant::QVariant(double val) noexcept : d(std::piecewise_construct_t{}, val) {} |
950 | QVariant::QVariant(float val) noexcept : d(std::piecewise_construct_t{}, val) {} |
951 | |
952 | QVariant::QVariant(const QByteArray &val) noexcept : d(std::piecewise_construct_t{}, val) {} |
953 | #ifndef QT_BOOTSTRAPPED |
954 | QVariant::QVariant(const QBitArray &val) noexcept : d(std::piecewise_construct_t{}, val) {} |
955 | #endif |
956 | QVariant::QVariant(const QString &val) noexcept : d(std::piecewise_construct_t{}, val) {} |
957 | QVariant::QVariant(QChar val) noexcept : d(std::piecewise_construct_t{}, val) {} |
958 | QVariant::QVariant(const QStringList &val) noexcept : d(std::piecewise_construct_t{}, val) {} |
959 | |
960 | QVariant::QVariant(QDate val) noexcept : d(std::piecewise_construct_t{}, val) {} |
961 | QVariant::QVariant(QTime val) noexcept : d(std::piecewise_construct_t{}, val) {} |
962 | QVariant::QVariant(const QDateTime &val) noexcept : d(std::piecewise_construct_t{}, val) {} |
963 | |
964 | QVariant::QVariant(const QList<QVariant> &list) noexcept : d(std::piecewise_construct_t{}, list) {} |
965 | QVariant::QVariant(const QMap<QString, QVariant> &map) noexcept : d(std::piecewise_construct_t{}, map) {} |
966 | QVariant::QVariant(const QHash<QString, QVariant> &hash) noexcept : d(std::piecewise_construct_t{}, hash) {} |
967 | |
968 | QVariant::QVariant(QLatin1StringView val) : QVariant(QString(val)) {} |
969 | |
970 | #if QT_CONFIG(easingcurve) |
971 | QVariant::QVariant(const QEasingCurve &val) : d(std::piecewise_construct_t{}, val) {} |
972 | #endif |
973 | #ifndef QT_NO_GEOM_VARIANT |
974 | QVariant::QVariant(QPoint pt) noexcept |
975 | : d(std::piecewise_construct_t{}, pt) {} |
976 | QVariant::QVariant(QPointF pt) noexcept(Private::FitsInInternalSize<sizeof(qreal) * 2>) |
977 | : d(std::piecewise_construct_t{}, pt) {} |
978 | QVariant::QVariant(QRect r) noexcept(Private::FitsInInternalSize<sizeof(int) * 4>) |
979 | : d(std::piecewise_construct_t{}, r) {} |
980 | QVariant::QVariant(QRectF r) noexcept(Private::FitsInInternalSize<sizeof(qreal) * 4>) |
981 | : d(std::piecewise_construct_t{}, r) {} |
982 | QVariant::QVariant(QLine l) noexcept(Private::FitsInInternalSize<sizeof(int) * 4>) |
983 | : d(std::piecewise_construct_t{}, l) {} |
984 | QVariant::QVariant(QLineF l) noexcept(Private::FitsInInternalSize<sizeof(qreal) * 4>) |
985 | : d(std::piecewise_construct_t{}, l) {} |
986 | QVariant::QVariant(QSize s) noexcept |
987 | : d(std::piecewise_construct_t{}, s) {} |
988 | QVariant::QVariant(QSizeF s) noexcept(Private::FitsInInternalSize<sizeof(qreal) * 2>) |
989 | : d(std::piecewise_construct_t{}, s) {} |
990 | #endif |
991 | #ifndef QT_BOOTSTRAPPED |
992 | QVariant::QVariant(const QUrl &u) noexcept : d(std::piecewise_construct_t{}, u) {} |
993 | #endif |
994 | QVariant::QVariant(const QLocale &l) noexcept : d(std::piecewise_construct_t{}, l) {} |
995 | #if QT_CONFIG(regularexpression) |
996 | QVariant::QVariant(const QRegularExpression &re) noexcept : d(std::piecewise_construct_t{}, re) {} |
997 | #endif // QT_CONFIG(regularexpression) |
998 | QVariant::QVariant(QUuid uuid) noexcept(Private::FitsInInternalSize<16>) : d(std::piecewise_construct_t{}, uuid) {} |
999 | #ifndef QT_BOOTSTRAPPED |
1000 | QVariant::QVariant(const QJsonValue &jsonValue) noexcept(Private::FitsInInternalSize<sizeof(CborValueStandIn)>) |
1001 | : d(std::piecewise_construct_t{}, jsonValue) |
1002 | { static_assert(sizeof(CborValueStandIn) == sizeof(QJsonValue)); } |
1003 | QVariant::QVariant(const QJsonObject &jsonObject) noexcept : d(std::piecewise_construct_t{}, jsonObject) {} |
1004 | QVariant::QVariant(const QJsonArray &jsonArray) noexcept : d(std::piecewise_construct_t{}, jsonArray) {} |
1005 | QVariant::QVariant(const QJsonDocument &jsonDocument) : d(std::piecewise_construct_t{}, jsonDocument) {} |
1006 | #endif // QT_BOOTSTRAPPED |
1007 | #if QT_CONFIG(itemmodel) |
1008 | QVariant::QVariant(const QModelIndex &modelIndex) noexcept(Private::FitsInInternalSize<8 + 2 * sizeof(quintptr)>) |
1009 | : d(std::piecewise_construct_t{}, modelIndex) {} |
1010 | QVariant::QVariant(const QPersistentModelIndex &modelIndex) : d(std::piecewise_construct_t{}, modelIndex) {} |
1011 | #endif |
1012 | |
1013 | /*! \fn QVariant::Type QVariant::type() const |
1014 | \deprecated [6.0] Use typeId() or metaType() instead. |
1015 | |
1016 | Returns the storage type of the value stored in the variant. |
1017 | Although this function is declared as returning QVariant::Type, |
1018 | the return value should be interpreted as QMetaType::Type. In |
1019 | particular, QVariant::UserType is returned here only if the value |
1020 | is equal or greater than QMetaType::User. |
1021 | |
1022 | Note that return values in the ranges QVariant::Char through |
1023 | QVariant::RegExp and QVariant::Font through QVariant::Transform |
1024 | correspond to the values in the ranges QMetaType::QChar through |
1025 | QMetaType::QRegularExpression and QMetaType::QFont through QMetaType::QQuaternion. |
1026 | |
1027 | Pay particular attention when working with char and QChar |
1028 | variants. Note that there is no QVariant constructor specifically |
1029 | for type char, but there is one for QChar. For a variant of type |
1030 | QChar, this function returns QVariant::Char, which is the same as |
1031 | QMetaType::QChar, but for a variant of type \c char, this function |
1032 | returns QMetaType::Char, which is \e not the same as |
1033 | QVariant::Char. |
1034 | |
1035 | Also note that the types \c void*, \c long, \c short, \c unsigned |
1036 | \c long, \c unsigned \c short, \c unsigned \c char, \c float, \c |
1037 | QObject*, and \c QWidget* are represented in QMetaType::Type but |
1038 | not in QVariant::Type, and they can be returned by this function. |
1039 | However, they are considered to be user defined types when tested |
1040 | against QVariant::Type. |
1041 | |
1042 | To test whether an instance of QVariant contains a data type that |
1043 | is compatible with the data type you are interested in, use |
1044 | canConvert(). |
1045 | |
1046 | \sa userType(), metaType() |
1047 | */ |
1048 | |
1049 | /*! \fn int QVariant::userType() const |
1050 | \fn int QVariant::typeId() const |
1051 | |
1052 | Returns the storage type of the value stored in the variant. This is |
1053 | the same as metaType().id(). |
1054 | |
1055 | \sa metaType() |
1056 | */ |
1057 | |
1058 | /*! |
1059 | \since 6.0 |
1060 | |
1061 | Returns the QMetaType of the value stored in the variant. |
1062 | */ |
1063 | QMetaType QVariant::metaType() const |
1064 | { |
1065 | return d.type(); |
1066 | } |
1067 | |
1068 | /*! |
1069 | Assigns the value of the variant \a variant to this variant. |
1070 | */ |
1071 | QVariant &QVariant::operator=(const QVariant &variant) |
1072 | { |
1073 | if (this == &variant) |
1074 | return *this; |
1075 | |
1076 | clear(); |
1077 | d = clonePrivate(other: variant.d); |
1078 | return *this; |
1079 | } |
1080 | |
1081 | /*! |
1082 | \fn void QVariant::swap(QVariant &other) |
1083 | \since 4.8 |
1084 | \memberswap{variant} |
1085 | */ |
1086 | |
1087 | /*! |
1088 | \fn void QVariant::detach() |
1089 | |
1090 | \internal |
1091 | */ |
1092 | |
1093 | void QVariant::detach() |
1094 | { |
1095 | if (!d.is_shared || d.data.shared->ref.loadRelaxed() == 1) |
1096 | return; |
1097 | |
1098 | Q_ASSERT(isValidMetaTypeForVariant(d.typeInterface(), constData())); |
1099 | Private dd(d.typeInterface()); |
1100 | // null variant is never shared; anything else is NonNull |
1101 | customConstruct<UseCopy, NonNull>(iface: d.typeInterface(), d: &dd, copy: constData()); |
1102 | if (!d.data.shared->ref.deref()) |
1103 | customClear(d: &d); |
1104 | d.data.shared = dd.data.shared; |
1105 | } |
1106 | |
1107 | /*! |
1108 | \fn bool QVariant::isDetached() const |
1109 | |
1110 | \internal |
1111 | */ |
1112 | |
1113 | /*! |
1114 | Returns the name of the type stored in the variant. The returned |
1115 | strings describe the C++ datatype used to store the data: for |
1116 | example, "QFont", "QString", or "QVariantList". An Invalid |
1117 | variant returns 0. |
1118 | */ |
1119 | const char *QVariant::typeName() const |
1120 | { |
1121 | return d.type().name(); |
1122 | } |
1123 | |
1124 | /*! |
1125 | Convert this variant to type QMetaType::UnknownType and free up any resources |
1126 | used. |
1127 | */ |
1128 | void QVariant::clear() |
1129 | { |
1130 | if (!d.is_shared || !d.data.shared->ref.deref()) |
1131 | customClear(d: &d); |
1132 | d = {}; |
1133 | } |
1134 | |
1135 | /*! |
1136 | \fn const char *QVariant::typeToName(int typeId) |
1137 | \deprecated [6.0] Use \c QMetaType(typeId).name() instead. |
1138 | |
1139 | Converts the int representation of the storage type, \a typeId, to |
1140 | its string representation. |
1141 | |
1142 | Returns \nullptr if the type is QMetaType::UnknownType or doesn't exist. |
1143 | */ |
1144 | |
1145 | /*! |
1146 | \fn QVariant::Type QVariant::nameToType(const char *name) |
1147 | \deprecated [6.0] Use \c QMetaType::fromName(name).id() instead |
1148 | |
1149 | Converts the string representation of the storage type given in \a |
1150 | name, to its enum representation. |
1151 | |
1152 | If the string representation cannot be converted to any enum |
1153 | representation, the variant is set to \c Invalid. |
1154 | */ |
1155 | |
1156 | #ifndef QT_NO_DATASTREAM |
1157 | enum { MapFromThreeCount = 36 }; |
1158 | static const ushort mapIdFromQt3ToCurrent[MapFromThreeCount] = |
1159 | { |
1160 | QMetaType::UnknownType, |
1161 | QMetaType::QVariantMap, |
1162 | QMetaType::QVariantList, |
1163 | QMetaType::QString, |
1164 | QMetaType::QStringList, |
1165 | QMetaType::QFont, |
1166 | QMetaType::QPixmap, |
1167 | QMetaType::QBrush, |
1168 | QMetaType::QRect, |
1169 | QMetaType::QSize, |
1170 | QMetaType::QColor, |
1171 | QMetaType::QPalette, |
1172 | 0, // ColorGroup |
1173 | QMetaType::QIcon, |
1174 | QMetaType::QPoint, |
1175 | QMetaType::QImage, |
1176 | QMetaType::Int, |
1177 | QMetaType::UInt, |
1178 | QMetaType::Bool, |
1179 | QMetaType::Double, |
1180 | 0, // Buggy ByteArray, QByteArray never had id == 20 |
1181 | QMetaType::QPolygon, |
1182 | QMetaType::QRegion, |
1183 | QMetaType::QBitmap, |
1184 | QMetaType::QCursor, |
1185 | QMetaType::QSizePolicy, |
1186 | QMetaType::QDate, |
1187 | QMetaType::QTime, |
1188 | QMetaType::QDateTime, |
1189 | QMetaType::QByteArray, |
1190 | QMetaType::QBitArray, |
1191 | #if QT_CONFIG(shortcut) |
1192 | QMetaType::QKeySequence, |
1193 | #else |
1194 | 0, // QKeySequence |
1195 | #endif |
1196 | QMetaType::QPen, |
1197 | QMetaType::LongLong, |
1198 | QMetaType::ULongLong, |
1199 | #if QT_CONFIG(easingcurve) |
1200 | QMetaType::QEasingCurve |
1201 | #endif |
1202 | }; |
1203 | |
1204 | // values needed to map Qt5 based type id's to Qt6 based ones |
1205 | constexpr int Qt5UserType = 1024; |
1206 | constexpr int Qt5LastCoreType = QMetaType::QCborMap; |
1207 | constexpr int Qt5FirstGuiType = 64; |
1208 | constexpr int Qt5LastGuiType = 87; |
1209 | constexpr int Qt5SizePolicy = 121; |
1210 | constexpr int Qt5RegExp = 27; |
1211 | constexpr int Qt5KeySequence = 75; |
1212 | constexpr int Qt5QQuaternion = 85; |
1213 | |
1214 | constexpr int Qt6ToQt5GuiTypeDelta = qToUnderlying(e: QMetaType::FirstGuiType) - Qt5FirstGuiType; |
1215 | |
1216 | /*! |
1217 | Internal function for loading a variant from stream \a s. Use the |
1218 | stream operators instead. |
1219 | |
1220 | \internal |
1221 | */ |
1222 | void QVariant::load(QDataStream &s) |
1223 | { |
1224 | clear(); |
1225 | |
1226 | quint32 typeId; |
1227 | s >> typeId; |
1228 | if (s.version() < QDataStream::Qt_4_0) { |
1229 | // map to Qt 5 ids |
1230 | if (typeId >= MapFromThreeCount) |
1231 | return; |
1232 | typeId = mapIdFromQt3ToCurrent[typeId]; |
1233 | } else if (s.version() < QDataStream::Qt_5_0) { |
1234 | // map to Qt 5 type ids |
1235 | if (typeId == 127 /* QVariant::UserType */) { |
1236 | typeId = Qt5UserType; |
1237 | } else if (typeId >= 128 && typeId != Qt5UserType) { |
1238 | // In Qt4 id == 128 was FirstExtCoreType. In Qt5 ExtCoreTypes set was merged to CoreTypes |
1239 | // by moving all ids down by 97. |
1240 | typeId -= 97; |
1241 | } else if (typeId == 75 /* QSizePolicy */) { |
1242 | typeId = Qt5SizePolicy; |
1243 | } else if (typeId > 75 && typeId <= 86) { |
1244 | // and as a result these types received lower ids too |
1245 | // QKeySequence QPen QTextLength QTextFormat QTransform QMatrix4x4 QVector2D QVector3D QVector4D QQuaternion |
1246 | typeId -=1; |
1247 | } |
1248 | } |
1249 | if (s.version() < QDataStream::Qt_6_0) { |
1250 | // map from Qt 5 to Qt 6 values |
1251 | if (typeId == Qt5UserType) { |
1252 | typeId = QMetaType::User; |
1253 | } else if (typeId >= Qt5FirstGuiType && typeId <= Qt5LastGuiType) { |
1254 | typeId += Qt6ToQt5GuiTypeDelta; |
1255 | } else if (typeId == Qt5SizePolicy) { |
1256 | typeId = QMetaType::QSizePolicy; |
1257 | } else if (typeId == Qt5RegExp) { |
1258 | typeId = QMetaType::fromName(name: "QRegExp").id(); |
1259 | } |
1260 | } |
1261 | |
1262 | qint8 is_null = false; |
1263 | if (s.version() >= QDataStream::Qt_4_2) |
1264 | s >> is_null; |
1265 | if (typeId == QMetaType::User) { |
1266 | QByteArray name; |
1267 | s >> name; |
1268 | typeId = QMetaType::fromName(name).id(); |
1269 | if (typeId == QMetaType::UnknownType) { |
1270 | s.setStatus(QDataStream::ReadCorruptData); |
1271 | qWarning(msg: "QVariant::load: unknown user type with name %s.", name.constData()); |
1272 | return; |
1273 | } |
1274 | } |
1275 | create(type: typeId, copy: nullptr); |
1276 | d.is_null = is_null; |
1277 | |
1278 | if (!isValid()) { |
1279 | if (s.version() < QDataStream::Qt_5_0) { |
1280 | // Since we wrote something, we should read something |
1281 | QString x; |
1282 | s >> x; |
1283 | } |
1284 | d.is_null = true; |
1285 | return; |
1286 | } |
1287 | |
1288 | // const cast is safe since we operate on a newly constructed variant |
1289 | void *data = const_cast<void *>(constData()); |
1290 | if (!d.type().load(stream&: s, data)) { |
1291 | s.setStatus(QDataStream::ReadCorruptData); |
1292 | qWarning(msg: "QVariant::load: unable to load type %d.", d.type().id()); |
1293 | } |
1294 | } |
1295 | |
1296 | /*! |
1297 | Internal function for saving a variant to the stream \a s. Use the |
1298 | stream operators instead. |
1299 | |
1300 | \internal |
1301 | */ |
1302 | void QVariant::save(QDataStream &s) const |
1303 | { |
1304 | quint32 typeId = d.type().id(); |
1305 | bool saveAsUserType = false; |
1306 | if (typeId >= QMetaType::User) { |
1307 | typeId = QMetaType::User; |
1308 | saveAsUserType = true; |
1309 | } |
1310 | if (s.version() < QDataStream::Qt_6_0) { |
1311 | // map to Qt 5 values |
1312 | if (typeId == QMetaType::User) { |
1313 | typeId = Qt5UserType; |
1314 | if (!strcmp(s1: d.type().name(), s2: "QRegExp")) { |
1315 | typeId = 27; // QRegExp in Qt 4/5 |
1316 | } |
1317 | } else if (typeId > Qt5LastCoreType && typeId <= QMetaType::LastCoreType) { |
1318 | // the type didn't exist in Qt 5 |
1319 | typeId = Qt5UserType; |
1320 | saveAsUserType = true; |
1321 | } else if (typeId >= QMetaType::FirstGuiType && typeId <= QMetaType::LastGuiType) { |
1322 | typeId -= Qt6ToQt5GuiTypeDelta; |
1323 | if (typeId > Qt5LastGuiType) { |
1324 | typeId = Qt5UserType; |
1325 | saveAsUserType = true; |
1326 | } |
1327 | } else if (typeId == QMetaType::QSizePolicy) { |
1328 | typeId = Qt5SizePolicy; |
1329 | } |
1330 | } |
1331 | if (s.version() < QDataStream::Qt_4_0) { |
1332 | int i; |
1333 | for (i = 0; i <= MapFromThreeCount - 1; ++i) { |
1334 | if (mapIdFromQt3ToCurrent[i] == typeId) { |
1335 | typeId = i; |
1336 | break; |
1337 | } |
1338 | } |
1339 | if (i >= MapFromThreeCount) { |
1340 | s << QVariant(); |
1341 | return; |
1342 | } |
1343 | } else if (s.version() < QDataStream::Qt_5_0) { |
1344 | if (typeId == Qt5UserType) { |
1345 | typeId = 127; // QVariant::UserType had this value in Qt4 |
1346 | saveAsUserType = true; |
1347 | } else if (typeId >= 128 - 97 && typeId <= Qt5LastCoreType) { |
1348 | // In Qt4 id == 128 was FirstExtCoreType. In Qt5 ExtCoreTypes set was merged to CoreTypes |
1349 | // by moving all ids down by 97. |
1350 | typeId += 97; |
1351 | } else if (typeId == Qt5SizePolicy) { |
1352 | typeId = 75; |
1353 | } else if (typeId >= Qt5KeySequence && typeId <= Qt5QQuaternion) { |
1354 | // and as a result these types received lower ids too |
1355 | typeId += 1; |
1356 | } else if (typeId > Qt5QQuaternion || typeId == QMetaType::QUuid) { |
1357 | // These existed in Qt 4 only as a custom type |
1358 | typeId = 127; |
1359 | saveAsUserType = true; |
1360 | } |
1361 | } |
1362 | const char *typeName = nullptr; |
1363 | if (saveAsUserType) { |
1364 | if (s.version() < QDataStream::Qt_6_0) |
1365 | typeName = QtMetaTypePrivate::typedefNameForType(type_d: d.type().d_ptr); |
1366 | if (!typeName) |
1367 | typeName = d.type().name(); |
1368 | } |
1369 | s << typeId; |
1370 | if (s.version() >= QDataStream::Qt_4_2) |
1371 | s << qint8(d.is_null); |
1372 | if (typeName) |
1373 | s << typeName; |
1374 | |
1375 | if (!isValid()) { |
1376 | if (s.version() < QDataStream::Qt_5_0) |
1377 | s << QString(); |
1378 | return; |
1379 | } |
1380 | |
1381 | if (!d.type().save(stream&: s, data: constData())) { |
1382 | qWarning(msg: "QVariant::save: unable to save type '%s' (type id: %d).\n", |
1383 | d.type().name(), d.type().id()); |
1384 | Q_ASSERT_X(false, "QVariant::save", "Invalid type to save"); |
1385 | } |
1386 | } |
1387 | |
1388 | /*! |
1389 | \since 4.4 |
1390 | \relates QVariant |
1391 | |
1392 | Reads a variant \a p from the stream \a s. |
1393 | |
1394 | \note If the stream contains types that aren't the built-in ones (see \l |
1395 | QMetaType::Type), those types must be registered using qRegisterMetaType() |
1396 | or QMetaType::registerType() before the variant can be properly loaded. If |
1397 | an unregistered type is found, QVariant will set the corrupt flag in the |
1398 | stream, stop processing and print a warning. For example, for QList<int> |
1399 | it would print the following: |
1400 | |
1401 | \quotation |
1402 | QVariant::load: unknown user type with name QList<int> |
1403 | \endquotation |
1404 | |
1405 | \sa{Serializing Qt Data Types}{Format of the QDataStream operators} |
1406 | */ |
1407 | QDataStream &operator>>(QDataStream &s, QVariant &p) |
1408 | { |
1409 | p.load(s); |
1410 | return s; |
1411 | } |
1412 | |
1413 | /*! |
1414 | Writes a variant \a p to the stream \a s. |
1415 | \relates QVariant |
1416 | |
1417 | \sa{Serializing Qt Data Types}{Format of the QDataStream operators} |
1418 | */ |
1419 | QDataStream &operator<<(QDataStream &s, const QVariant &p) |
1420 | { |
1421 | p.save(s); |
1422 | return s; |
1423 | } |
1424 | |
1425 | /*! \fn QDataStream& operator>>(QDataStream &s, QVariant::Type &p) |
1426 | \relates QVariant |
1427 | \deprecated [6.0] Stream QMetaType::Type instead. |
1428 | |
1429 | Reads a variant type \a p in enum representation from the stream \a s. |
1430 | */ |
1431 | |
1432 | /*! \fn QDataStream& operator<<(QDataStream &s, const QVariant::Type p) |
1433 | \relates QVariant |
1434 | \deprecated [6.0] Stream QMetaType::Type instead. |
1435 | |
1436 | Writes a variant type \a p to the stream \a s. |
1437 | */ |
1438 | #endif //QT_NO_DATASTREAM |
1439 | |
1440 | /*! |
1441 | \fn bool QVariant::isValid() const |
1442 | |
1443 | Returns \c true if the storage type of this variant is not |
1444 | QMetaType::UnknownType; otherwise returns \c false. |
1445 | */ |
1446 | |
1447 | /*! |
1448 | \fn QStringList QVariant::toStringList() const |
1449 | |
1450 | Returns the variant as a QStringList if the variant has userType() |
1451 | \l QMetaType::QStringList, \l QMetaType::QString, or |
1452 | \l QMetaType::QVariantList of a type that can be converted to QString; |
1453 | otherwise returns an empty list. |
1454 | |
1455 | \sa canConvert(), convert() |
1456 | */ |
1457 | QStringList QVariant::toStringList() const |
1458 | { |
1459 | return qvariant_cast<QStringList>(v: *this); |
1460 | } |
1461 | |
1462 | /*! |
1463 | Returns the variant as a QString if the variant has a userType() |
1464 | including, but not limited to: |
1465 | |
1466 | \l QMetaType::QString, \l QMetaType::Bool, \l QMetaType::QByteArray, |
1467 | \l QMetaType::QChar, \l QMetaType::QDate, \l QMetaType::QDateTime, |
1468 | \l QMetaType::Double, \l QMetaType::Int, \l QMetaType::LongLong, |
1469 | \l QMetaType::QStringList, \l QMetaType::QTime, \l QMetaType::UInt, or |
1470 | \l QMetaType::ULongLong. |
1471 | |
1472 | Calling QVariant::toString() on an unsupported variant returns an empty |
1473 | string. |
1474 | |
1475 | \sa canConvert(), convert() |
1476 | */ |
1477 | QString QVariant::toString() const |
1478 | { |
1479 | return qvariant_cast<QString>(v: *this); |
1480 | } |
1481 | |
1482 | /*! |
1483 | Returns the variant as a QVariantMap if the variant has type() \l |
1484 | QMetaType::QVariantMap. If it doesn't, QVariant will attempt to |
1485 | convert the type to a map and then return it. This will succeed for |
1486 | any type that has registered a converter to QVariantMap or which was |
1487 | declared as a associative container using |
1488 | \l{Q_DECLARE_ASSOCIATIVE_CONTAINER_METATYPE}. If none of those |
1489 | conditions are true, this function will return an empty map. |
1490 | |
1491 | \sa canConvert(), convert() |
1492 | */ |
1493 | QVariantMap QVariant::toMap() const |
1494 | { |
1495 | return qvariant_cast<QVariantMap>(v: *this); |
1496 | } |
1497 | |
1498 | /*! |
1499 | Returns the variant as a QHash<QString, QVariant> if the variant |
1500 | has type() \l QMetaType::QVariantHash; otherwise returns an empty map. |
1501 | |
1502 | \sa canConvert(), convert() |
1503 | */ |
1504 | QVariantHash QVariant::toHash() const |
1505 | { |
1506 | return qvariant_cast<QVariantHash>(v: *this); |
1507 | } |
1508 | |
1509 | /*! |
1510 | \fn QDate QVariant::toDate() const |
1511 | |
1512 | Returns the variant as a QDate if the variant has userType() |
1513 | \l QMetaType::QDate, \l QMetaType::QDateTime, or \l QMetaType::QString; |
1514 | otherwise returns an invalid date. |
1515 | |
1516 | If the type() is \l QMetaType::QString, an invalid date will be returned if |
1517 | the string cannot be parsed as a Qt::ISODate format date. |
1518 | |
1519 | \sa canConvert(), convert() |
1520 | */ |
1521 | QDate QVariant::toDate() const |
1522 | { |
1523 | return qvariant_cast<QDate>(v: *this); |
1524 | } |
1525 | |
1526 | /*! |
1527 | \fn QTime QVariant::toTime() const |
1528 | |
1529 | Returns the variant as a QTime if the variant has userType() |
1530 | \l QMetaType::QTime, \l QMetaType::QDateTime, or \l QMetaType::QString; |
1531 | otherwise returns an invalid time. |
1532 | |
1533 | If the type() is \l QMetaType::QString, an invalid time will be returned if |
1534 | the string cannot be parsed as a Qt::ISODate format time. |
1535 | |
1536 | \sa canConvert(), convert() |
1537 | */ |
1538 | QTime QVariant::toTime() const |
1539 | { |
1540 | return qvariant_cast<QTime>(v: *this); |
1541 | } |
1542 | |
1543 | /*! |
1544 | \fn QDateTime QVariant::toDateTime() const |
1545 | |
1546 | Returns the variant as a QDateTime if the variant has userType() |
1547 | \l QMetaType::QDateTime, \l QMetaType::QDate, or \l QMetaType::QString; |
1548 | otherwise returns an invalid date/time. |
1549 | |
1550 | If the type() is \l QMetaType::QString, an invalid date/time will be |
1551 | returned if the string cannot be parsed as a Qt::ISODate format date/time. |
1552 | |
1553 | \sa canConvert(), convert() |
1554 | */ |
1555 | QDateTime QVariant::toDateTime() const |
1556 | { |
1557 | return qvariant_cast<QDateTime>(v: *this); |
1558 | } |
1559 | |
1560 | /*! |
1561 | \since 4.7 |
1562 | \fn QEasingCurve QVariant::toEasingCurve() const |
1563 | |
1564 | Returns the variant as a QEasingCurve if the variant has userType() |
1565 | \l QMetaType::QEasingCurve; otherwise returns a default easing curve. |
1566 | |
1567 | \sa canConvert(), convert() |
1568 | */ |
1569 | #if QT_CONFIG(easingcurve) |
1570 | QEasingCurve QVariant::toEasingCurve() const |
1571 | { |
1572 | return qvariant_cast<QEasingCurve>(v: *this); |
1573 | } |
1574 | #endif |
1575 | |
1576 | /*! |
1577 | \fn QByteArray QVariant::toByteArray() const |
1578 | |
1579 | Returns the variant as a QByteArray if the variant has userType() |
1580 | \l QMetaType::QByteArray or \l QMetaType::QString (converted using |
1581 | QString::fromUtf8()); otherwise returns an empty byte array. |
1582 | |
1583 | \sa canConvert(), convert() |
1584 | */ |
1585 | QByteArray QVariant::toByteArray() const |
1586 | { |
1587 | return qvariant_cast<QByteArray>(v: *this); |
1588 | } |
1589 | |
1590 | #ifndef QT_NO_GEOM_VARIANT |
1591 | /*! |
1592 | \fn QPoint QVariant::toPoint() const |
1593 | |
1594 | Returns the variant as a QPoint if the variant has userType() |
1595 | \l QMetaType::QPoint or \l QMetaType::QPointF; otherwise returns a null |
1596 | QPoint. |
1597 | |
1598 | \sa canConvert(), convert() |
1599 | */ |
1600 | QPoint QVariant::toPoint() const |
1601 | { |
1602 | return qvariant_cast<QPoint>(v: *this); |
1603 | } |
1604 | |
1605 | /*! |
1606 | \fn QRect QVariant::toRect() const |
1607 | |
1608 | Returns the variant as a QRect if the variant has userType() |
1609 | \l QMetaType::QRect; otherwise returns an invalid QRect. |
1610 | |
1611 | \sa canConvert(), convert() |
1612 | */ |
1613 | QRect QVariant::toRect() const |
1614 | { |
1615 | return qvariant_cast<QRect>(v: *this); |
1616 | } |
1617 | |
1618 | /*! |
1619 | \fn QSize QVariant::toSize() const |
1620 | |
1621 | Returns the variant as a QSize if the variant has userType() |
1622 | \l QMetaType::QSize; otherwise returns an invalid QSize. |
1623 | |
1624 | \sa canConvert(), convert() |
1625 | */ |
1626 | QSize QVariant::toSize() const |
1627 | { |
1628 | return qvariant_cast<QSize>(v: *this); |
1629 | } |
1630 | |
1631 | /*! |
1632 | \fn QSizeF QVariant::toSizeF() const |
1633 | |
1634 | Returns the variant as a QSizeF if the variant has userType() \l |
1635 | QMetaType::QSizeF; otherwise returns an invalid QSizeF. |
1636 | |
1637 | \sa canConvert(), convert() |
1638 | */ |
1639 | QSizeF QVariant::toSizeF() const |
1640 | { |
1641 | return qvariant_cast<QSizeF>(v: *this); |
1642 | } |
1643 | |
1644 | /*! |
1645 | \fn QRectF QVariant::toRectF() const |
1646 | |
1647 | Returns the variant as a QRectF if the variant has userType() |
1648 | \l QMetaType::QRect or \l QMetaType::QRectF; otherwise returns an invalid |
1649 | QRectF. |
1650 | |
1651 | \sa canConvert(), convert() |
1652 | */ |
1653 | QRectF QVariant::toRectF() const |
1654 | { |
1655 | return qvariant_cast<QRectF>(v: *this); |
1656 | } |
1657 | |
1658 | /*! |
1659 | \fn QLineF QVariant::toLineF() const |
1660 | |
1661 | Returns the variant as a QLineF if the variant has userType() |
1662 | \l QMetaType::QLineF; otherwise returns an invalid QLineF. |
1663 | |
1664 | \sa canConvert(), convert() |
1665 | */ |
1666 | QLineF QVariant::toLineF() const |
1667 | { |
1668 | return qvariant_cast<QLineF>(v: *this); |
1669 | } |
1670 | |
1671 | /*! |
1672 | \fn QLine QVariant::toLine() const |
1673 | |
1674 | Returns the variant as a QLine if the variant has userType() |
1675 | \l QMetaType::QLine; otherwise returns an invalid QLine. |
1676 | |
1677 | \sa canConvert(), convert() |
1678 | */ |
1679 | QLine QVariant::toLine() const |
1680 | { |
1681 | return qvariant_cast<QLine>(v: *this); |
1682 | } |
1683 | |
1684 | /*! |
1685 | \fn QPointF QVariant::toPointF() const |
1686 | |
1687 | Returns the variant as a QPointF if the variant has userType() \l |
1688 | QMetaType::QPoint or \l QMetaType::QPointF; otherwise returns a null |
1689 | QPointF. |
1690 | |
1691 | \sa canConvert(), convert() |
1692 | */ |
1693 | QPointF QVariant::toPointF() const |
1694 | { |
1695 | return qvariant_cast<QPointF>(v: *this); |
1696 | } |
1697 | |
1698 | #endif // QT_NO_GEOM_VARIANT |
1699 | |
1700 | #ifndef QT_BOOTSTRAPPED |
1701 | /*! |
1702 | \fn QUrl QVariant::toUrl() const |
1703 | |
1704 | Returns the variant as a QUrl if the variant has userType() |
1705 | \l QMetaType::QUrl; otherwise returns an invalid QUrl. |
1706 | |
1707 | \sa canConvert(), convert() |
1708 | */ |
1709 | QUrl QVariant::toUrl() const |
1710 | { |
1711 | return qvariant_cast<QUrl>(v: *this); |
1712 | } |
1713 | #endif |
1714 | |
1715 | /*! |
1716 | \fn QLocale QVariant::toLocale() const |
1717 | |
1718 | Returns the variant as a QLocale if the variant has userType() |
1719 | \l QMetaType::QLocale; otherwise returns an invalid QLocale. |
1720 | |
1721 | \sa canConvert(), convert() |
1722 | */ |
1723 | QLocale QVariant::toLocale() const |
1724 | { |
1725 | return qvariant_cast<QLocale>(v: *this); |
1726 | } |
1727 | |
1728 | #if QT_CONFIG(regularexpression) |
1729 | /*! |
1730 | \fn QRegularExpression QVariant::toRegularExpression() const |
1731 | \since 5.0 |
1732 | |
1733 | Returns the variant as a QRegularExpression if the variant has userType() \l |
1734 | QRegularExpression; otherwise returns an empty QRegularExpression. |
1735 | |
1736 | \sa canConvert(), convert() |
1737 | */ |
1738 | QRegularExpression QVariant::toRegularExpression() const |
1739 | { |
1740 | return qvariant_cast<QRegularExpression>(v: *this); |
1741 | } |
1742 | #endif // QT_CONFIG(regularexpression) |
1743 | |
1744 | #if QT_CONFIG(itemmodel) |
1745 | /*! |
1746 | \since 5.0 |
1747 | |
1748 | Returns the variant as a QModelIndex if the variant has userType() \l |
1749 | QModelIndex; otherwise returns a default constructed QModelIndex. |
1750 | |
1751 | \sa canConvert(), convert(), toPersistentModelIndex() |
1752 | */ |
1753 | QModelIndex QVariant::toModelIndex() const |
1754 | { |
1755 | return qvariant_cast<QModelIndex>(v: *this); |
1756 | } |
1757 | |
1758 | /*! |
1759 | \since 5.5 |
1760 | |
1761 | Returns the variant as a QPersistentModelIndex if the variant has userType() \l |
1762 | QPersistentModelIndex; otherwise returns a default constructed QPersistentModelIndex. |
1763 | |
1764 | \sa canConvert(), convert(), toModelIndex() |
1765 | */ |
1766 | QPersistentModelIndex QVariant::toPersistentModelIndex() const |
1767 | { |
1768 | return qvariant_cast<QPersistentModelIndex>(v: *this); |
1769 | } |
1770 | #endif // QT_CONFIG(itemmodel) |
1771 | |
1772 | /*! |
1773 | \since 5.0 |
1774 | |
1775 | Returns the variant as a QUuid if the variant has type() |
1776 | \l QMetaType::QUuid, \l QMetaType::QByteArray or \l QMetaType::QString; |
1777 | otherwise returns a default-constructed QUuid. |
1778 | |
1779 | \sa canConvert(), convert() |
1780 | */ |
1781 | QUuid QVariant::toUuid() const |
1782 | { |
1783 | return qvariant_cast<QUuid>(v: *this); |
1784 | } |
1785 | |
1786 | #ifndef QT_BOOTSTRAPPED |
1787 | /*! |
1788 | \since 5.0 |
1789 | |
1790 | Returns the variant as a QJsonValue if the variant has userType() \l |
1791 | QJsonValue; otherwise returns a default constructed QJsonValue. |
1792 | |
1793 | \sa canConvert(), convert() |
1794 | */ |
1795 | QJsonValue QVariant::toJsonValue() const |
1796 | { |
1797 | return qvariant_cast<QJsonValue>(v: *this); |
1798 | } |
1799 | |
1800 | /*! |
1801 | \since 5.0 |
1802 | |
1803 | Returns the variant as a QJsonObject if the variant has userType() \l |
1804 | QJsonObject; otherwise returns a default constructed QJsonObject. |
1805 | |
1806 | \sa canConvert(), convert() |
1807 | */ |
1808 | QJsonObject QVariant::toJsonObject() const |
1809 | { |
1810 | return qvariant_cast<QJsonObject>(v: *this); |
1811 | } |
1812 | |
1813 | /*! |
1814 | \since 5.0 |
1815 | |
1816 | Returns the variant as a QJsonArray if the variant has userType() \l |
1817 | QJsonArray; otherwise returns a default constructed QJsonArray. |
1818 | |
1819 | \sa canConvert(), convert() |
1820 | */ |
1821 | QJsonArray QVariant::toJsonArray() const |
1822 | { |
1823 | return qvariant_cast<QJsonArray>(v: *this); |
1824 | } |
1825 | |
1826 | /*! |
1827 | \since 5.0 |
1828 | |
1829 | Returns the variant as a QJsonDocument if the variant has userType() \l |
1830 | QJsonDocument; otherwise returns a default constructed QJsonDocument. |
1831 | |
1832 | \sa canConvert(), convert() |
1833 | */ |
1834 | QJsonDocument QVariant::toJsonDocument() const |
1835 | { |
1836 | return qvariant_cast<QJsonDocument>(v: *this); |
1837 | } |
1838 | #endif // QT_BOOTSTRAPPED |
1839 | |
1840 | /*! |
1841 | \fn QChar QVariant::toChar() const |
1842 | |
1843 | Returns the variant as a QChar if the variant has userType() |
1844 | \l QMetaType::QChar, \l QMetaType::Int, or \l QMetaType::UInt; otherwise |
1845 | returns an invalid QChar. |
1846 | |
1847 | \sa canConvert(), convert() |
1848 | */ |
1849 | QChar QVariant::toChar() const |
1850 | { |
1851 | return qvariant_cast<QChar>(v: *this); |
1852 | } |
1853 | |
1854 | #ifndef QT_BOOTSTRAPPED |
1855 | /*! |
1856 | Returns the variant as a QBitArray if the variant has userType() |
1857 | \l QMetaType::QBitArray; otherwise returns an empty bit array. |
1858 | |
1859 | \sa canConvert(), convert() |
1860 | */ |
1861 | QBitArray QVariant::toBitArray() const |
1862 | { |
1863 | return qvariant_cast<QBitArray>(v: *this); |
1864 | } |
1865 | #endif // QT_BOOTSTRAPPED |
1866 | |
1867 | template <typename T> |
1868 | inline T qNumVariantToHelper(const QVariant::Private &d, bool *ok) |
1869 | { |
1870 | QMetaType t = QMetaType::fromType<T>(); |
1871 | if (ok) |
1872 | *ok = true; |
1873 | |
1874 | if (d.type() == t) |
1875 | return d.get<T>(); |
1876 | |
1877 | T ret = 0; |
1878 | bool success = QMetaType::convert(d.type(), d.storage(), t, &ret); |
1879 | if (ok) |
1880 | *ok = success; |
1881 | return ret; |
1882 | } |
1883 | |
1884 | /*! |
1885 | Returns the variant as an int if the variant has userType() |
1886 | \l QMetaType::Int, \l QMetaType::Bool, \l QMetaType::QByteArray, |
1887 | \l QMetaType::QChar, \l QMetaType::Double, \l QMetaType::LongLong, |
1888 | \l QMetaType::QString, \l QMetaType::UInt, or \l QMetaType::ULongLong; |
1889 | otherwise returns 0. |
1890 | |
1891 | If \a ok is non-null: \c{*}\a{ok} is set to true if the value could be |
1892 | converted to an int; otherwise \c{*}\a{ok} is set to false. |
1893 | |
1894 | \b{Warning:} If the value is convertible to a \l QMetaType::LongLong but is |
1895 | too large to be represented in an int, the resulting arithmetic overflow |
1896 | will not be reflected in \a ok. A simple workaround is to use |
1897 | QString::toInt(). |
1898 | |
1899 | \sa canConvert(), convert() |
1900 | */ |
1901 | int QVariant::toInt(bool *ok) const |
1902 | { |
1903 | return qNumVariantToHelper<int>(d, ok); |
1904 | } |
1905 | |
1906 | /*! |
1907 | Returns the variant as an unsigned int if the variant has userType() |
1908 | \l QMetaType::UInt, \l QMetaType::Bool, \l QMetaType::QByteArray, |
1909 | \l QMetaType::QChar, \l QMetaType::Double, \l QMetaType::Int, |
1910 | \l QMetaType::LongLong, \l QMetaType::QString, or \l QMetaType::ULongLong; |
1911 | otherwise returns 0. |
1912 | |
1913 | If \a ok is non-null: \c{*}\a{ok} is set to true if the value could be |
1914 | converted to an unsigned int; otherwise \c{*}\a{ok} is set to false. |
1915 | |
1916 | \b{Warning:} If the value is convertible to a \l QMetaType::ULongLong but is |
1917 | too large to be represented in an unsigned int, the resulting arithmetic |
1918 | overflow will not be reflected in \a ok. A simple workaround is to use |
1919 | QString::toUInt(). |
1920 | |
1921 | \sa canConvert(), convert() |
1922 | */ |
1923 | uint QVariant::toUInt(bool *ok) const |
1924 | { |
1925 | return qNumVariantToHelper<uint>(d, ok); |
1926 | } |
1927 | |
1928 | /*! |
1929 | Returns the variant as a long long int if the variant has userType() |
1930 | \l QMetaType::LongLong, \l QMetaType::Bool, \l QMetaType::QByteArray, |
1931 | \l QMetaType::QChar, \l QMetaType::Double, \l QMetaType::Int, |
1932 | \l QMetaType::QString, \l QMetaType::UInt, or \l QMetaType::ULongLong; |
1933 | otherwise returns 0. |
1934 | |
1935 | If \a ok is non-null: \c{*}\c{ok} is set to true if the value could be |
1936 | converted to an int; otherwise \c{*}\c{ok} is set to false. |
1937 | |
1938 | \sa canConvert(), convert() |
1939 | */ |
1940 | qlonglong QVariant::toLongLong(bool *ok) const |
1941 | { |
1942 | return qNumVariantToHelper<qlonglong>(d, ok); |
1943 | } |
1944 | |
1945 | /*! |
1946 | Returns the variant as an unsigned long long int if the |
1947 | variant has type() \l QMetaType::ULongLong, \l QMetaType::Bool, |
1948 | \l QMetaType::QByteArray, \l QMetaType::QChar, \l QMetaType::Double, |
1949 | \l QMetaType::Int, \l QMetaType::LongLong, \l QMetaType::QString, or |
1950 | \l QMetaType::UInt; otherwise returns 0. |
1951 | |
1952 | If \a ok is non-null: \c{*}\a{ok} is set to true if the value could be |
1953 | converted to an int; otherwise \c{*}\a{ok} is set to false. |
1954 | |
1955 | \sa canConvert(), convert() |
1956 | */ |
1957 | qulonglong QVariant::toULongLong(bool *ok) const |
1958 | { |
1959 | return qNumVariantToHelper<qulonglong>(d, ok); |
1960 | } |
1961 | |
1962 | /*! |
1963 | Returns the variant as a bool if the variant has userType() Bool. |
1964 | |
1965 | Returns \c true if the variant has userType() \l QMetaType::Bool, |
1966 | \l QMetaType::QChar, \l QMetaType::Double, \l QMetaType::Int, |
1967 | \l QMetaType::LongLong, \l QMetaType::UInt, or \l QMetaType::ULongLong and |
1968 | the value is non-zero, or if the variant has type \l QMetaType::QString or |
1969 | \l QMetaType::QByteArray and its lower-case content is not one of the |
1970 | following: empty, "0" or "false"; otherwise returns \c false. |
1971 | |
1972 | \sa canConvert(), convert() |
1973 | */ |
1974 | bool QVariant::toBool() const |
1975 | { |
1976 | auto boolType = QMetaType::fromType<bool>(); |
1977 | if (d.type() == boolType) |
1978 | return d.get<bool>(); |
1979 | |
1980 | bool res = false; |
1981 | QMetaType::convert(fromType: d.type(), from: constData(), toType: boolType, to: &res); |
1982 | return res; |
1983 | } |
1984 | |
1985 | /*! |
1986 | Returns the variant as a double if the variant has userType() |
1987 | \l QMetaType::Double, \l QMetaType::Float, \l QMetaType::Bool, |
1988 | \l QMetaType::QByteArray, \l QMetaType::Int, \l QMetaType::LongLong, |
1989 | \l QMetaType::QString, \l QMetaType::UInt, or \l QMetaType::ULongLong; |
1990 | otherwise returns 0.0. |
1991 | |
1992 | If \a ok is non-null: \c{*}\a{ok} is set to true if the value could be |
1993 | converted to a double; otherwise \c{*}\a{ok} is set to false. |
1994 | |
1995 | \sa canConvert(), convert() |
1996 | */ |
1997 | double QVariant::toDouble(bool *ok) const |
1998 | { |
1999 | return qNumVariantToHelper<double>(d, ok); |
2000 | } |
2001 | |
2002 | /*! |
2003 | Returns the variant as a float if the variant has userType() |
2004 | \l QMetaType::Double, \l QMetaType::Float, \l QMetaType::Bool, |
2005 | \l QMetaType::QByteArray, \l QMetaType::Int, \l QMetaType::LongLong, |
2006 | \l QMetaType::QString, \l QMetaType::UInt, or \l QMetaType::ULongLong; |
2007 | otherwise returns 0.0. |
2008 | |
2009 | \since 4.6 |
2010 | |
2011 | If \a ok is non-null: \c{*}\a{ok} is set to true if the value could be |
2012 | converted to a double; otherwise \c{*}\a{ok} is set to false. |
2013 | |
2014 | \sa canConvert(), convert() |
2015 | */ |
2016 | float QVariant::toFloat(bool *ok) const |
2017 | { |
2018 | return qNumVariantToHelper<float>(d, ok); |
2019 | } |
2020 | |
2021 | /*! |
2022 | Returns the variant as a qreal if the variant has userType() |
2023 | \l QMetaType::Double, \l QMetaType::Float, \l QMetaType::Bool, |
2024 | \l QMetaType::QByteArray, \l QMetaType::Int, \l QMetaType::LongLong, |
2025 | \l QMetaType::QString, \l QMetaType::UInt, or \l QMetaType::ULongLong; |
2026 | otherwise returns 0.0. |
2027 | |
2028 | \since 4.6 |
2029 | |
2030 | If \a ok is non-null: \c{*}\a{ok} is set to true if the value could be |
2031 | converted to a double; otherwise \c{*}\a{ok} is set to false. |
2032 | |
2033 | \sa canConvert(), convert() |
2034 | */ |
2035 | qreal QVariant::toReal(bool *ok) const |
2036 | { |
2037 | return qNumVariantToHelper<qreal>(d, ok); |
2038 | } |
2039 | |
2040 | /*! |
2041 | Returns the variant as a QVariantList if the variant has userType() \l |
2042 | QMetaType::QVariantList. If it doesn't, QVariant will attempt to convert |
2043 | the type to a list and then return it. This will succeed for any type that |
2044 | has registered a converter to QVariantList or which was declared as a |
2045 | sequential container using \l{Q_DECLARE_SEQUENTIAL_CONTAINER_METATYPE}. If |
2046 | none of those conditions are true, this function will return an empty |
2047 | list. |
2048 | |
2049 | \sa canConvert(), convert() |
2050 | */ |
2051 | QVariantList QVariant::toList() const |
2052 | { |
2053 | return qvariant_cast<QVariantList>(v: *this); |
2054 | } |
2055 | |
2056 | /*! |
2057 | \fn bool QVariant::canConvert(int targetTypeId) const |
2058 | \overload |
2059 | \deprecated [6.0] Use \c canConvert(QMetaType(targetTypeId)) instead. |
2060 | |
2061 | \sa QMetaType::canConvert() |
2062 | */ |
2063 | |
2064 | /*! |
2065 | \fn bool QVariant::canConvert(QMetaType type) const |
2066 | \since 6.0 |
2067 | |
2068 | Returns \c true if the variant's type can be cast to the requested |
2069 | type, \a type. Such casting is done automatically when calling the |
2070 | toInt(), toBool(), ... methods. |
2071 | |
2072 | \sa QMetaType::canConvert() |
2073 | */ |
2074 | |
2075 | |
2076 | /*! |
2077 | \fn bool QVariant::convert(int targetTypeId) |
2078 | \deprecated [6.0] Use \c convert(QMetaType(targetTypeId)) instead. |
2079 | |
2080 | Casts the variant to the requested type, \a targetTypeId. If the cast cannot be |
2081 | done, the variant is still changed to the requested type, but is left in a cleared |
2082 | null state similar to that constructed by QVariant(Type). |
2083 | |
2084 | Returns \c true if the current type of the variant was successfully cast; |
2085 | otherwise returns \c false. |
2086 | |
2087 | A QVariant containing a pointer to a type derived from QObject will also convert |
2088 | and return true for this function if a qobject_cast to the type described |
2089 | by \a targetTypeId would succeed. Note that this only works for QObject subclasses |
2090 | which use the Q_OBJECT macro. |
2091 | |
2092 | \note converting QVariants that are null due to not being initialized or having |
2093 | failed a previous conversion will always fail, changing the type, remaining null, |
2094 | and returning \c false. |
2095 | |
2096 | \sa canConvert(), clear() |
2097 | */ |
2098 | |
2099 | /*! |
2100 | Casts the variant to the requested type, \a targetType. If the cast cannot be |
2101 | done, the variant is still changed to the requested type, but is left in a cleared |
2102 | null state similar to that constructed by QVariant(Type). |
2103 | |
2104 | Returns \c true if the current type of the variant was successfully cast; |
2105 | otherwise returns \c false. |
2106 | |
2107 | A QVariant containing a pointer to a type derived from QObject will also convert |
2108 | and return true for this function if a qobject_cast to the type described |
2109 | by \a targetType would succeed. Note that this only works for QObject subclasses |
2110 | which use the Q_OBJECT macro. |
2111 | |
2112 | \note converting QVariants that are null due to not being initialized or having |
2113 | failed a previous conversion will always fail, changing the type, remaining null, |
2114 | and returning \c false. |
2115 | |
2116 | \since 6.0 |
2117 | |
2118 | \sa canConvert(), clear() |
2119 | */ |
2120 | |
2121 | bool QVariant::convert(QMetaType targetType) |
2122 | { |
2123 | if (d.type() == targetType) |
2124 | return targetType.isValid(); |
2125 | |
2126 | QVariant oldValue = *this; |
2127 | |
2128 | clear(); |
2129 | create(type: targetType, copy: nullptr); |
2130 | if (!oldValue.canConvert(targetType)) |
2131 | return false; |
2132 | |
2133 | // Fail if the value is not initialized or was forced null by a previous failed convert. |
2134 | if (oldValue.d.is_null && oldValue.d.type().id() != QMetaType::Nullptr) |
2135 | return false; |
2136 | |
2137 | bool ok = QMetaType::convert(fromType: oldValue.d.type(), from: oldValue.constData(), toType: targetType, to: data()); |
2138 | d.is_null = !ok; |
2139 | return ok; |
2140 | } |
2141 | |
2142 | /*! |
2143 | \fn bool QVariant::convert(int type, void *ptr) const |
2144 | \internal |
2145 | Created for qvariant_cast() usage |
2146 | */ |
2147 | bool QVariant::convert(int type, void *ptr) const |
2148 | { |
2149 | return QMetaType::convert(fromType: d.type(), from: constData(), toType: QMetaType(type), to: ptr); |
2150 | } |
2151 | |
2152 | /*! |
2153 | \internal |
2154 | */ |
2155 | bool QVariant::view(int type, void *ptr) |
2156 | { |
2157 | return QMetaType::view(fromType: d.type(), from: data(), toType: QMetaType(type), to: ptr); |
2158 | } |
2159 | |
2160 | /*! |
2161 | \fn bool QVariant::operator==(const QVariant &lhs, const QVariant &rhs) |
2162 | |
2163 | Returns \c true if \a lhs and \a rhs are equal; otherwise returns \c false. |
2164 | |
2165 | QVariant uses the equality operator of the type() contained to check for |
2166 | equality. |
2167 | |
2168 | Variants of different types will always compare as not equal with a few |
2169 | exceptions: |
2170 | |
2171 | \list |
2172 | \li If both types are numeric types (integers and floatins point numbers) |
2173 | Qt will compare those types using standard C++ type promotion rules. |
2174 | \li If one type is numeric and the other one a QString, Qt will try to |
2175 | convert the QString to a matching numeric type and if successful compare |
2176 | those. |
2177 | \li If both variants contain pointers to QObject derived types, QVariant |
2178 | will check whether the types are related and point to the same object. |
2179 | \endlist |
2180 | |
2181 | The result of the function is not affected by the result of QVariant::isNull, |
2182 | which means that two values can be equal even if one of them is null and |
2183 | another is not. |
2184 | */ |
2185 | |
2186 | /*! |
2187 | \fn bool QVariant::operator!=(const QVariant &lhs, const QVariant &rhs) |
2188 | |
2189 | Returns \c false if \a lhs and \a rhs are equal; otherwise returns \c true. |
2190 | |
2191 | QVariant uses the equality operator of the type() contained to check for |
2192 | equality. |
2193 | |
2194 | Variants of different types will always compare as not equal with a few |
2195 | exceptions: |
2196 | |
2197 | \list |
2198 | \li If both types are numeric types (integers and floatins point numbers) |
2199 | Qt will compare those types using standard C++ type promotion rules. |
2200 | \li If one type is numeric and the other one a QString, Qt will try to |
2201 | convert the QString to a matching numeric type and if successful compare |
2202 | those. |
2203 | \li If both variants contain pointers to QObject derived types, QVariant |
2204 | will check whether the types are related and point to the same object. |
2205 | \endlist |
2206 | */ |
2207 | |
2208 | static bool qIsNumericType(uint tp) |
2209 | { |
2210 | static const qulonglong numericTypeBits = |
2211 | Q_UINT64_C(1) << QMetaType::QString | |
2212 | Q_UINT64_C(1) << QMetaType::Bool | |
2213 | Q_UINT64_C(1) << QMetaType::Double | |
2214 | Q_UINT64_C(1) << QMetaType::Float | |
2215 | Q_UINT64_C(1) << QMetaType::Char | |
2216 | Q_UINT64_C(1) << QMetaType::Char16 | |
2217 | Q_UINT64_C(1) << QMetaType::Char32 | |
2218 | Q_UINT64_C(1) << QMetaType::SChar | |
2219 | Q_UINT64_C(1) << QMetaType::UChar | |
2220 | Q_UINT64_C(1) << QMetaType::Short | |
2221 | Q_UINT64_C(1) << QMetaType::UShort | |
2222 | Q_UINT64_C(1) << QMetaType::Int | |
2223 | Q_UINT64_C(1) << QMetaType::UInt | |
2224 | Q_UINT64_C(1) << QMetaType::Long | |
2225 | Q_UINT64_C(1) << QMetaType::ULong | |
2226 | Q_UINT64_C(1) << QMetaType::LongLong | |
2227 | Q_UINT64_C(1) << QMetaType::ULongLong; |
2228 | return tp < (CHAR_BIT * sizeof numericTypeBits) ? numericTypeBits & (Q_UINT64_C(1) << tp) : false; |
2229 | } |
2230 | |
2231 | static bool qIsFloatingPoint(uint tp) |
2232 | { |
2233 | return tp == QMetaType::Double || tp == QMetaType::Float || tp == QMetaType::Float16; |
2234 | } |
2235 | |
2236 | static bool canBeNumericallyCompared(const QtPrivate::QMetaTypeInterface *iface1, |
2237 | const QtPrivate::QMetaTypeInterface *iface2) |
2238 | { |
2239 | if (!iface1 || !iface2) |
2240 | return false; |
2241 | |
2242 | // We don't need QMetaType::id() here because the type Id is always stored |
2243 | // directly for all built-in types. |
2244 | bool isNumeric1 = qIsNumericType(tp: iface1->typeId); |
2245 | bool isNumeric2 = qIsNumericType(tp: iface2->typeId); |
2246 | |
2247 | // if they're both numeric (or QString), then they can be compared |
2248 | if (isNumeric1 && isNumeric2) |
2249 | return true; |
2250 | |
2251 | bool isEnum1 = iface1->flags & QMetaType::IsEnumeration; |
2252 | bool isEnum2 = iface2->flags & QMetaType::IsEnumeration; |
2253 | |
2254 | // if both are enums, we can only compare if they are the same enum |
2255 | // (the language does allow comparing two different enum types, but that's |
2256 | // usually considered poor coding and produces a warning) |
2257 | if (isEnum1 && isEnum2) |
2258 | return QMetaType(iface1) == QMetaType(iface2); |
2259 | |
2260 | // if one is an enum and the other is a numeric, we can compare too |
2261 | if (isEnum1 && isNumeric2) |
2262 | return true; |
2263 | if (isNumeric1 && isEnum2) |
2264 | return true; |
2265 | |
2266 | // we need at least one enum and one numeric... |
2267 | return false; |
2268 | } |
2269 | |
2270 | static int numericTypePromotion(const QtPrivate::QMetaTypeInterface *iface1, |
2271 | const QtPrivate::QMetaTypeInterface *iface2) |
2272 | { |
2273 | Q_ASSERT(canBeNumericallyCompared(iface1, iface2)); |
2274 | |
2275 | // We don't need QMetaType::id() here because the type Id is always stored |
2276 | // directly for the types we're comparing against below. |
2277 | uint t1 = iface1->typeId; |
2278 | uint t2 = iface2->typeId; |
2279 | |
2280 | if ((t1 == QMetaType::Bool && t2 == QMetaType::QString) || |
2281 | (t2 == QMetaType::Bool && t1 == QMetaType::QString)) |
2282 | return QMetaType::Bool; |
2283 | |
2284 | // C++ integral ranks: (4.13 Integer conversion rank [conv.rank]) |
2285 | // bool < signed char < short < int < long < long long |
2286 | // unsigneds have the same rank as their signed counterparts |
2287 | // C++ integral promotion rules (4.5 Integral Promotions [conv.prom]) |
2288 | // - any type with rank less than int can be converted to int or unsigned int |
2289 | // 5 Expressions [expr] paragraph 9: |
2290 | // - if either operand is double, the other shall be converted to double |
2291 | // - " " float, " " " float |
2292 | // - if both operands have the same type, no further conversion is needed. |
2293 | // - if both are signed or if both are unsigned, convert to the one with highest rank |
2294 | // - if the unsigned has higher or same rank, convert the signed to the unsigned one |
2295 | // - if the signed can represent all values of the unsigned, convert to the signed |
2296 | // - otherwise, convert to the unsigned corresponding to the rank of the signed |
2297 | |
2298 | // floating point: we deviate from the C++ standard by always using qreal |
2299 | if (qIsFloatingPoint(tp: t1) || qIsFloatingPoint(tp: t2)) |
2300 | return QMetaType::QReal; |
2301 | |
2302 | auto isUnsigned = [](uint tp) { |
2303 | // only types for which sizeof(T) >= sizeof(int); lesser ones promote to int |
2304 | return tp == QMetaType::ULongLong || tp == QMetaType::ULong || |
2305 | tp == QMetaType::UInt || tp == QMetaType::Char32; |
2306 | }; |
2307 | bool isUnsigned1 = isUnsigned(t1); |
2308 | bool isUnsigned2 = isUnsigned(t2); |
2309 | |
2310 | // integral rules: |
2311 | // 1) if either type is a 64-bit unsigned, compare as 64-bit unsigned |
2312 | if (isUnsigned1 && iface1->size > sizeof(int)) |
2313 | return QMetaType::ULongLong; |
2314 | if (isUnsigned2 && iface2->size > sizeof(int)) |
2315 | return QMetaType::ULongLong; |
2316 | |
2317 | // 2) if either type is 64-bit, compare as 64-bit signed |
2318 | if (iface1->size > sizeof(int) || iface2->size > sizeof(int)) |
2319 | return QMetaType::LongLong; |
2320 | |
2321 | // 3) if either type is 32-bit unsigned, compare as 32-bit unsigned |
2322 | if (isUnsigned1 || isUnsigned2) |
2323 | return QMetaType::UInt; |
2324 | |
2325 | // 4) otherwise, just do int promotion |
2326 | return QMetaType::Int; |
2327 | } |
2328 | |
2329 | template <typename Numeric> static QPartialOrdering spaceShip(Numeric lhs, Numeric rhs) |
2330 | { |
2331 | if (lhs == rhs) |
2332 | return QPartialOrdering::Equivalent; |
2333 | if constexpr (std::numeric_limits<Numeric>::has_quiet_NaN) { |
2334 | if (std::isnan(lhs) || std::isnan(rhs)) |
2335 | return QPartialOrdering::Unordered; |
2336 | } |
2337 | |
2338 | bool smaller; |
2339 | if constexpr (std::is_same_v<Numeric, QObject *>) |
2340 | smaller = std::less<QObject *>()(lhs, rhs); // can't use less all the time because of bool |
2341 | else |
2342 | smaller = lhs < rhs; |
2343 | return smaller ? QPartialOrdering::Less : QPartialOrdering::Greater; |
2344 | } |
2345 | |
2346 | static QPartialOrdering integralCompare(uint promotedType, const QVariant::Private *d1, const QVariant::Private *d2) |
2347 | { |
2348 | // use toLongLong to retrieve the data, it gets us all the bits |
2349 | std::optional<qlonglong> l1 = qConvertToNumber(d: d1, allowStringToBool: promotedType == QMetaType::Bool); |
2350 | std::optional<qlonglong> l2 = qConvertToNumber(d: d2, allowStringToBool: promotedType == QMetaType::Bool); |
2351 | if (!l1 || !l2) |
2352 | return QPartialOrdering::Unordered; |
2353 | if (promotedType == QMetaType::UInt) |
2354 | return spaceShip<uint>(lhs: *l1, rhs: *l2); |
2355 | if (promotedType == QMetaType::LongLong) |
2356 | return spaceShip<qlonglong>(lhs: *l1, rhs: *l2); |
2357 | if (promotedType == QMetaType::ULongLong) |
2358 | return spaceShip<qulonglong>(lhs: *l1, rhs: *l2); |
2359 | |
2360 | return spaceShip<int>(lhs: *l1, rhs: *l2); |
2361 | } |
2362 | |
2363 | static QPartialOrdering numericCompare(const QVariant::Private *d1, const QVariant::Private *d2) |
2364 | { |
2365 | uint promotedType = numericTypePromotion(iface1: d1->typeInterface(), iface2: d2->typeInterface()); |
2366 | if (promotedType != QMetaType::QReal) |
2367 | return integralCompare(promotedType, d1, d2); |
2368 | |
2369 | // floating point comparison |
2370 | const auto r1 = qConvertToRealNumber(d: d1); |
2371 | const auto r2 = qConvertToRealNumber(d: d2); |
2372 | if (!r1 || !r2) |
2373 | return QPartialOrdering::Unordered; |
2374 | if (*r1 == *r2) |
2375 | return QPartialOrdering::Equivalent; |
2376 | |
2377 | return spaceShip(lhs: *r1, rhs: *r2); |
2378 | } |
2379 | |
2380 | #ifndef QT_BOOTSTRAPPED |
2381 | static bool qvCanConvertMetaObject(QMetaType fromType, QMetaType toType) |
2382 | { |
2383 | if ((fromType.flags() & QMetaType::PointerToQObject) |
2384 | && (toType.flags() & QMetaType::PointerToQObject)) { |
2385 | const QMetaObject *f = fromType.metaObject(); |
2386 | const QMetaObject *t = toType.metaObject(); |
2387 | return f && t && (f->inherits(metaObject: t) || t->inherits(metaObject: f)); |
2388 | } |
2389 | return false; |
2390 | } |
2391 | |
2392 | static QPartialOrdering pointerCompare(const QVariant::Private *d1, const QVariant::Private *d2) |
2393 | { |
2394 | return spaceShip<QObject *>(lhs: d1->get<QObject *>(), rhs: d2->get<QObject *>()); |
2395 | } |
2396 | #endif |
2397 | |
2398 | /*! |
2399 | \internal |
2400 | */ |
2401 | bool QVariant::equals(const QVariant &v) const |
2402 | { |
2403 | auto metatype = d.type(); |
2404 | |
2405 | if (metatype != v.metaType()) { |
2406 | // try numeric comparisons, with C++ type promotion rules (no conversion) |
2407 | if (canBeNumericallyCompared(iface1: metatype.iface(), iface2: v.d.type().iface())) |
2408 | return numericCompare(d1: &d, d2: &v.d) == QPartialOrdering::Equivalent; |
2409 | #ifndef QT_BOOTSTRAPPED |
2410 | // if both types are related pointers to QObjects, check if they point to the same object |
2411 | if (qvCanConvertMetaObject(fromType: metatype, toType: v.metaType())) |
2412 | return pointerCompare(d1: &d, d2: &v.d) == QPartialOrdering::Equivalent; |
2413 | #endif |
2414 | return false; |
2415 | } |
2416 | |
2417 | // For historical reasons: QVariant() == QVariant() |
2418 | if (!metatype.isValid()) |
2419 | return true; |
2420 | |
2421 | return metatype.equals(lhs: d.storage(), rhs: v.d.storage()); |
2422 | } |
2423 | |
2424 | /*! |
2425 | Compares the objects at \a lhs and \a rhs for ordering. |
2426 | |
2427 | Returns QPartialOrdering::Unordered if comparison is not supported |
2428 | or the values are unordered. Otherwise, returns |
2429 | QPartialOrdering::Less, QPartialOrdering::Equivalent or |
2430 | QPartialOrdering::Greater if \a lhs is less than, equivalent |
2431 | to or greater than \a rhs, respectively. |
2432 | |
2433 | If the variants contain data with a different metatype, the values are considered |
2434 | unordered unless they are both of numeric or pointer types, where regular numeric or |
2435 | pointer comparison rules will be used. |
2436 | \note: If a numeric comparison is done and at least one value is NaN, QPartialOrdering::Unordered |
2437 | is returned. |
2438 | |
2439 | If both variants contain data of the same metatype, the method will use the |
2440 | QMetaType::compare method to determine the ordering of the two variants, which can |
2441 | also indicate that it can't establish an ordering between the two values. |
2442 | |
2443 | \since 6.0 |
2444 | \sa QMetaType::compare(), QMetaType::isOrdered() |
2445 | */ |
2446 | QPartialOrdering QVariant::compare(const QVariant &lhs, const QVariant &rhs) |
2447 | { |
2448 | QMetaType t = lhs.d.type(); |
2449 | if (t != rhs.d.type()) { |
2450 | // try numeric comparisons, with C++ type promotion rules (no conversion) |
2451 | if (canBeNumericallyCompared(iface1: lhs.d.type().iface(), iface2: rhs.d.type().iface())) |
2452 | return numericCompare(d1: &lhs.d, d2: &rhs.d); |
2453 | #ifndef QT_BOOTSTRAPPED |
2454 | if (qvCanConvertMetaObject(fromType: lhs.metaType(), toType: rhs.metaType())) |
2455 | return pointerCompare(d1: &lhs.d, d2: &rhs.d); |
2456 | #endif |
2457 | return QPartialOrdering::Unordered; |
2458 | } |
2459 | return t.compare(lhs: lhs.constData(), rhs: rhs.constData()); |
2460 | } |
2461 | |
2462 | /*! |
2463 | \fn const void *QVariant::constData() const |
2464 | \fn const void* QVariant::data() const |
2465 | |
2466 | Returns a pointer to the contained object as a generic void* that cannot be |
2467 | written to. |
2468 | |
2469 | \sa get_if(), QMetaType |
2470 | */ |
2471 | |
2472 | /*! |
2473 | Returns a pointer to the contained object as a generic void* that can be |
2474 | written to. |
2475 | |
2476 | This function detaches the QVariant. When called on a \l{isNull}{null-QVariant}, |
2477 | the QVariant will not be null after the call. |
2478 | |
2479 | \sa get_if(), QMetaType |
2480 | */ |
2481 | void *QVariant::data() |
2482 | { |
2483 | detach(); |
2484 | // set is_null to false, as the caller is likely to write some data into this variant |
2485 | d.is_null = false; |
2486 | return const_cast<void *>(constData()); |
2487 | } |
2488 | |
2489 | /*! |
2490 | \since 6.6 |
2491 | \fn template <typename T> const T* QVariant::get_if(const QVariant *v) |
2492 | \fn template <typename T> T* QVariant::get_if(QVariant *v) |
2493 | |
2494 | If \a v contains an object of type \c T, returns a pointer to the contained |
2495 | object, otherwise returns \nullptr. |
2496 | |
2497 | The overload taking a mutable \a v detaches \a v: When called on a |
2498 | \l{isNull()}{null} \a v with matching type \c T, \a v will not be null |
2499 | after the call. |
2500 | |
2501 | These functions are provided for compatibility with \c{std::variant}. |
2502 | |
2503 | \sa data() |
2504 | */ |
2505 | |
2506 | /*! |
2507 | \since 6.6 |
2508 | \fn template <typename T> T &QVariant::get(QVariant &v) |
2509 | \fn template <typename T> const T &QVariant::get(const QVariant &v) |
2510 | \fn template <typename T> T &&QVariant::get(QVariant &&v) |
2511 | \fn template <typename T> const T &&QVariant::get(const QVariant &&v) |
2512 | |
2513 | If \a v contains an object of type \c T, returns a reference to the contained |
2514 | object, otherwise the call has undefined behavior. |
2515 | |
2516 | The overloads taking a mutable \a v detach \a v: When called on a |
2517 | \l{isNull()}{null} \a v with matching type \c T, \a v will not be null |
2518 | after the call. |
2519 | |
2520 | These functions are provided for compatibility with \c{std::variant}. |
2521 | |
2522 | \sa get_if(), data() |
2523 | */ |
2524 | |
2525 | /*! |
2526 | Returns \c true if this is a null variant, false otherwise. |
2527 | |
2528 | A variant is considered null if it contains no initialized value or a null pointer. |
2529 | |
2530 | \note This behavior has been changed from Qt 5, where isNull() would also |
2531 | return true if the variant contained an object of a builtin type with an isNull() |
2532 | method that returned true for that object. |
2533 | |
2534 | \sa convert() |
2535 | */ |
2536 | bool QVariant::isNull() const |
2537 | { |
2538 | if (d.is_null || !metaType().isValid()) |
2539 | return true; |
2540 | if (metaType().flags() & QMetaType::IsPointer) |
2541 | return d.get<void *>() == nullptr; |
2542 | return false; |
2543 | } |
2544 | |
2545 | #ifndef QT_NO_DEBUG_STREAM |
2546 | QDebug QVariant::qdebugHelper(QDebug dbg) const |
2547 | { |
2548 | QDebugStateSaver saver(dbg); |
2549 | const uint typeId = d.type().id(); |
2550 | dbg.nospace() << "QVariant("; |
2551 | if (typeId != QMetaType::UnknownType) { |
2552 | dbg << d.type().name() << ", "; |
2553 | bool streamed = d.type().debugStream(dbg, rhs: d.storage()); |
2554 | if (!streamed && canConvert<QString>()) |
2555 | dbg << toString(); |
2556 | } else { |
2557 | dbg << "Invalid"; |
2558 | } |
2559 | dbg << ')'; |
2560 | return dbg; |
2561 | } |
2562 | |
2563 | QVariant QVariant::moveConstruct(QMetaType type, void *data) |
2564 | { |
2565 | QVariant var; |
2566 | var.d = QVariant::Private(type.d_ptr); |
2567 | customConstruct<ForceMove, NonNull>(iface: type.d_ptr, d: &var.d, copy: data); |
2568 | return var; |
2569 | } |
2570 | |
2571 | QVariant QVariant::copyConstruct(QMetaType type, const void *data) |
2572 | { |
2573 | QVariant var; |
2574 | var.d = QVariant::Private(type.d_ptr); |
2575 | customConstruct<UseCopy, NonNull>(iface: type.d_ptr, d: &var.d, copy: data); |
2576 | return var; |
2577 | } |
2578 | |
2579 | #if QT_DEPRECATED_SINCE(6, 0) |
2580 | QT_WARNING_PUSH |
2581 | QT_WARNING_DISABLE_DEPRECATED |
2582 | |
2583 | QDebug operator<<(QDebug dbg, const QVariant::Type p) |
2584 | { |
2585 | QDebugStateSaver saver(dbg); |
2586 | dbg.nospace() << "QVariant::" |
2587 | << (int(p) != int(QMetaType::UnknownType) |
2588 | ? QMetaType(p).name() |
2589 | : "Invalid"); |
2590 | return dbg; |
2591 | } |
2592 | |
2593 | QT_WARNING_POP |
2594 | #endif |
2595 | |
2596 | #endif |
2597 | |
2598 | /*! \fn template<typename T, typename = std::enable_if_t<!std::is_same_v<std::decay_t<T>, QVariant>>> void QVariant::setValue(T &&value) |
2599 | |
2600 | Stores a copy of \a value. If \c{T} is a type that QVariant |
2601 | doesn't support, QMetaType is used to store the value. A compile |
2602 | error will occur if QMetaType doesn't handle the type. |
2603 | |
2604 | Example: |
2605 | |
2606 | \snippet code/src_corelib_kernel_qvariant.cpp 4 |
2607 | |
2608 | \sa value(), fromValue(), canConvert() |
2609 | */ |
2610 | |
2611 | /*! \fn void QVariant::setValue(const QVariant &value) |
2612 | |
2613 | Copies \a value over this QVariant. It is equivalent to simply |
2614 | assigning \a value to this QVariant. |
2615 | */ |
2616 | |
2617 | /*! \fn void QVariant::setValue(QVariant &&value) |
2618 | |
2619 | Moves \a value over this QVariant. It is equivalent to simply |
2620 | move assigning \a value to this QVariant. |
2621 | */ |
2622 | |
2623 | /*! \fn template<typename T> T QVariant::value() const & |
2624 | |
2625 | Returns the stored value converted to the template type \c{T}. |
2626 | Call canConvert() to find out whether a type can be converted. |
2627 | If the value cannot be converted, a \l{default-constructed value} |
2628 | will be returned. |
2629 | |
2630 | If the type \c{T} is supported by QVariant, this function behaves |
2631 | exactly as toString(), toInt() etc. |
2632 | |
2633 | Example: |
2634 | |
2635 | \snippet code/src_corelib_kernel_qvariant.cpp 5 |
2636 | |
2637 | If the QVariant contains a pointer to a type derived from QObject then |
2638 | \c{T} may be any QObject type. If the pointer stored in the QVariant can be |
2639 | qobject_cast to T, then that result is returned. Otherwise \nullptr is |
2640 | returned. Note that this only works for QObject subclasses which use |
2641 | the Q_OBJECT macro. |
2642 | |
2643 | If the QVariant contains a sequential container and \c{T} is QVariantList, the |
2644 | elements of the container will be converted into \l {QVariant}s and returned as a QVariantList. |
2645 | |
2646 | \snippet code/src_corelib_kernel_qvariant.cpp 9 |
2647 | |
2648 | \sa setValue(), fromValue(), canConvert(), Q_DECLARE_SEQUENTIAL_CONTAINER_METATYPE() |
2649 | */ |
2650 | |
2651 | /*! \fn template<typename T> T QVariant::view() |
2652 | |
2653 | Returns a mutable view of template type \c{T} on the stored value. |
2654 | Call canView() to find out whether such a view is supported. |
2655 | If no such view can be created, returns the stored value converted to the |
2656 | template type \c{T}. Call canConvert() to find out whether a type can be |
2657 | converted. If the value can neither be viewed nor converted, a |
2658 | \l{default-constructed value} will be returned. |
2659 | |
2660 | \sa canView(), Q_DECLARE_SEQUENTIAL_CONTAINER_METATYPE() |
2661 | */ |
2662 | |
2663 | /*! \fn template<typename T> bool QVariant::canConvert() const |
2664 | |
2665 | Returns \c true if the variant can be converted to the template type \c{T}, |
2666 | otherwise false. |
2667 | |
2668 | Example: |
2669 | |
2670 | \snippet code/src_corelib_kernel_qvariant.cpp 6 |
2671 | |
2672 | A QVariant containing a pointer to a type derived from QObject will also return true for this |
2673 | function if a qobject_cast to the template type \c{T} would succeed. Note that this only works |
2674 | for QObject subclasses which use the Q_OBJECT macro. |
2675 | |
2676 | \sa convert() |
2677 | */ |
2678 | |
2679 | /*! \fn template<typename T> bool QVariant::canView() const |
2680 | |
2681 | Returns \c true if a mutable view of the template type \c{T} can be created on this variant, |
2682 | otherwise \c false. |
2683 | |
2684 | \sa value() |
2685 | */ |
2686 | |
2687 | /*! \fn template<typename T> static QVariant QVariant::fromValue(const T &value) |
2688 | |
2689 | Returns a QVariant containing a copy of \a value. Behaves |
2690 | exactly like setValue() otherwise. |
2691 | |
2692 | Example: |
2693 | |
2694 | \snippet code/src_corelib_kernel_qvariant.cpp 7 |
2695 | |
2696 | \sa setValue(), value() |
2697 | */ |
2698 | |
2699 | /*! \fn template<typename T, QVariant::if_rvalue<T> = true> static QVariant QVariant::fromValue(T &&value) |
2700 | |
2701 | \since 6.6 |
2702 | \overload |
2703 | */ |
2704 | |
2705 | /*! \fn template<typename... Types> QVariant QVariant::fromStdVariant(const std::variant<Types...> &value) |
2706 | \since 5.11 |
2707 | |
2708 | Returns a QVariant with the type and value of the active variant of \a value. If |
2709 | the active type is std::monostate a default QVariant is returned. |
2710 | |
2711 | \note With this method you do not need to register the variant as a Qt metatype, |
2712 | since the std::variant is resolved before being stored. The component types |
2713 | should be registered however. |
2714 | |
2715 | \sa fromValue() |
2716 | */ |
2717 | |
2718 | /*! |
2719 | \fn template<typename... Types> QVariant QVariant::fromStdVariant(std::variant<Types...> &&value) |
2720 | \since 6.6 |
2721 | \overload |
2722 | */ |
2723 | |
2724 | |
2725 | /*! |
2726 | \since 6.7 |
2727 | |
2728 | Creates a variant of type \a type, and initializes it with |
2729 | a copy of \c{*copy} if \a copy is not \nullptr (in which case, \a copy |
2730 | must point to an object of type \a type). |
2731 | |
2732 | Note that you have to pass the address of the object you want stored. |
2733 | |
2734 | Usually, you never have to use this constructor, use QVariant::fromValue() |
2735 | instead to construct variants from the pointer types represented by |
2736 | \c QMetaType::VoidStar, and \c QMetaType::QObjectStar. |
2737 | |
2738 | If \a type does not support copy construction and \a copy is not \nullptr, |
2739 | the variant will be invalid. Similarly, if \a copy is \nullptr and |
2740 | \a type does not support default construction, the variant will be |
2741 | invalid. |
2742 | |
2743 | Returns the QVariant created as described above. |
2744 | |
2745 | \sa QVariant::fromValue(), QMetaType::Type |
2746 | */ |
2747 | QVariant QVariant::fromMetaType(QMetaType type, const void *copy) |
2748 | { |
2749 | QVariant result; |
2750 | type.registerType(); |
2751 | const auto iface = type.iface(); |
2752 | if (isValidMetaTypeForVariant(iface, copy)) { |
2753 | result.d = Private(iface); |
2754 | customConstruct(iface, d: &result.d, copy); |
2755 | } |
2756 | return result; |
2757 | } |
2758 | |
2759 | /*! |
2760 | \fn template<typename T> T qvariant_cast(const QVariant &value) |
2761 | \relates QVariant |
2762 | |
2763 | Returns the given \a value converted to the template type \c{T}. |
2764 | |
2765 | This function is equivalent to QVariant::value(). |
2766 | |
2767 | \sa QVariant::value() |
2768 | */ |
2769 | |
2770 | /*! |
2771 | \fn template<typename T> T QVariant::qvariant_cast(QVariant &&value) |
2772 | \overload |
2773 | \since 6.7 |
2774 | |
2775 | Returns the given \a value converted to the template type \c{T}. |
2776 | */ |
2777 | |
2778 | /*! \fn template<typename T> T qVariantValue(const QVariant &value) |
2779 | \relates QVariant |
2780 | \deprecated |
2781 | |
2782 | Returns the given \a value converted to the template type \c{T}. |
2783 | |
2784 | This function is equivalent to |
2785 | \l{QVariant::value()}{QVariant::value}<T>(\a value). |
2786 | |
2787 | \note This function was provided as a workaround for MSVC 6 |
2788 | which did not support member template functions. It is advised |
2789 | to use the other form in new code. |
2790 | |
2791 | \sa QVariant::value(), qvariant_cast() |
2792 | */ |
2793 | |
2794 | /*! \fn bool qVariantCanConvert(const QVariant &value) |
2795 | \relates QVariant |
2796 | \deprecated |
2797 | |
2798 | Returns \c true if the given \a value can be converted to the |
2799 | template type specified; otherwise returns \c false. |
2800 | |
2801 | This function is equivalent to QVariant::canConvert(\a value). |
2802 | |
2803 | \note This function was provided as a workaround for MSVC 6 |
2804 | which did not support member template functions. It is advised |
2805 | to use the other form in new code. |
2806 | |
2807 | \sa QVariant::canConvert() |
2808 | */ |
2809 | |
2810 | /*! |
2811 | \typedef QVariantList |
2812 | \relates QVariant |
2813 | |
2814 | Synonym for QList<QVariant>. |
2815 | */ |
2816 | |
2817 | /*! |
2818 | \typedef QVariantMap |
2819 | \relates QVariant |
2820 | |
2821 | Synonym for QMap<QString, QVariant>. |
2822 | */ |
2823 | |
2824 | /*! |
2825 | \typedef QVariantHash |
2826 | \relates QVariant |
2827 | \since 4.5 |
2828 | |
2829 | Synonym for QHash<QString, QVariant>. |
2830 | */ |
2831 | |
2832 | /*! |
2833 | \typedef QVariant::DataPtr |
2834 | \internal |
2835 | */ |
2836 | /*! \typedef QVariant::f_construct |
2837 | \internal |
2838 | */ |
2839 | |
2840 | /*! \typedef QVariant::f_clear |
2841 | \internal |
2842 | */ |
2843 | |
2844 | /*! \typedef QVariant::f_null |
2845 | \internal |
2846 | */ |
2847 | |
2848 | /*! \typedef QVariant::f_load |
2849 | \internal |
2850 | */ |
2851 | |
2852 | /*! \typedef QVariant::f_save |
2853 | \internal |
2854 | */ |
2855 | |
2856 | /*! \typedef QVariant::f_compare |
2857 | \internal |
2858 | */ |
2859 | |
2860 | /*! \typedef QVariant::f_convert |
2861 | \internal |
2862 | */ |
2863 | |
2864 | /*! \typedef QVariant::f_canConvert |
2865 | \internal |
2866 | */ |
2867 | |
2868 | /*! \typedef QVariant::f_debugStream |
2869 | \internal |
2870 | */ |
2871 | |
2872 | /*! |
2873 | \fn DataPtr &QVariant::data_ptr() |
2874 | \internal |
2875 | */ |
2876 | |
2877 | /*! |
2878 | \fn const DataPtr &QVariant::data_ptr() const |
2879 | \internal |
2880 | */ |
2881 | |
2882 | /*! |
2883 | \internal |
2884 | */ |
2885 | const void *QtPrivate::QVariantTypeCoercer::convert(const QVariant &value, const QMetaType &type) |
2886 | { |
2887 | if (type == QMetaType::fromType<QVariant>()) |
2888 | return &value; |
2889 | |
2890 | if (type == value.metaType()) |
2891 | return value.constData(); |
2892 | |
2893 | if (value.canConvert(targetType: type)) { |
2894 | converted = value; |
2895 | if (converted.convert(targetType: type)) |
2896 | return converted.constData(); |
2897 | } |
2898 | |
2899 | return nullptr; |
2900 | } |
2901 | |
2902 | /*! |
2903 | \internal |
2904 | */ |
2905 | const void *QtPrivate::QVariantTypeCoercer::coerce(const QVariant &value, const QMetaType &type) |
2906 | { |
2907 | if (const void *result = convert(value, type)) |
2908 | return result; |
2909 | |
2910 | converted = QVariant(type); |
2911 | return converted.constData(); |
2912 | } |
2913 | |
2914 | /*! |
2915 | \class QVariantRef |
2916 | \since 6.0 |
2917 | \inmodule QtCore |
2918 | \brief The QVariantRef acts as a non-const reference to a QVariant. |
2919 | |
2920 | As the generic iterators don't actually instantiate a QVariant on each |
2921 | step, they cannot return a reference to one from operator*(). QVariantRef |
2922 | provides the same functionality as an actual reference to a QVariant would, |
2923 | but is backed by a pointer given as template parameter. The template is |
2924 | implemented for pointers of type QSequentialIterator and |
2925 | QAssociativeIterator. |
2926 | */ |
2927 | |
2928 | /*! |
2929 | \fn template<typename Pointer> QVariantRef<Pointer>::QVariantRef(const Pointer *pointer) |
2930 | |
2931 | Creates a QVariantRef from an \a pointer. |
2932 | */ |
2933 | |
2934 | /*! |
2935 | \fn template<typename Pointer> QVariantRef<Pointer> &QVariantRef<Pointer>::operator=(const QVariant &value) |
2936 | |
2937 | Assigns a new \a value to the value pointed to by the pointer this |
2938 | QVariantRef refers to. |
2939 | */ |
2940 | |
2941 | /*! |
2942 | \fn template<typename Pointer> QVariantRef<Pointer> &QVariantRef<Pointer>::operator=(const QVariantRef &value) |
2943 | |
2944 | Assigns a new \a value to the value pointed to by the pointer this |
2945 | QVariantRef refers to. |
2946 | */ |
2947 | |
2948 | /*! |
2949 | \fn template<typename Pointer> QVariantRef<Pointer> &QVariantRef<Pointer>::operator=(QVariantRef &&value) |
2950 | |
2951 | Assigns a new \a value to the value pointed to by the pointer this |
2952 | QVariantRef refers to. |
2953 | */ |
2954 | |
2955 | /*! |
2956 | \fn template<typename Pointer> QVariantRef<Pointer>::operator QVariant() const |
2957 | |
2958 | Resolves the QVariantRef to an actual QVariant. |
2959 | */ |
2960 | |
2961 | /*! |
2962 | \fn template<typename Pointer> void swap(QVariantRef<Pointer> a, QVariantRef<Pointer> b) |
2963 | |
2964 | Swaps the values pointed to by the pointers the QVariantRefs |
2965 | \a a and \a b refer to. |
2966 | */ |
2967 | |
2968 | /*! |
2969 | \class QVariantConstPointer |
2970 | \since 6.0 |
2971 | \inmodule QtCore |
2972 | \brief Emulated const pointer to QVariant based on a pointer. |
2973 | |
2974 | QVariantConstPointer wraps a QVariant and returns it from its operator*(). |
2975 | This makes it suitable as replacement for an actual const pointer. We cannot |
2976 | return an actual const pointer from generic iterators as the iterators don't |
2977 | hold an actual QVariant. |
2978 | */ |
2979 | |
2980 | /*! |
2981 | Constructs a QVariantConstPointer from a \a variant. |
2982 | */ |
2983 | QVariantConstPointer::QVariantConstPointer(QVariant variant) |
2984 | : m_variant(std::move(variant)) |
2985 | { |
2986 | } |
2987 | |
2988 | /*! |
2989 | Dereferences the QVariantConstPointer to retrieve its internal QVariant. |
2990 | */ |
2991 | QVariant QVariantConstPointer::operator*() const |
2992 | { |
2993 | return m_variant; |
2994 | } |
2995 | |
2996 | /*! |
2997 | Returns a const pointer to the QVariant, conforming to the |
2998 | conventions for operator->(). |
2999 | */ |
3000 | const QVariant *QVariantConstPointer::operator->() const |
3001 | { |
3002 | return &m_variant; |
3003 | } |
3004 | |
3005 | /*! |
3006 | \class QVariantPointer |
3007 | \since 6.0 |
3008 | \inmodule QtCore |
3009 | \brief QVariantPointer is a template class that emulates a pointer to QVariant based on a pointer. |
3010 | |
3011 | QVariantConstPointer wraps a pointer and returns QVariantRef to it from its |
3012 | operator*(). This makes it suitable as replacement for an actual pointer. We |
3013 | cannot return an actual pointer from generic iterators as the iterators don't |
3014 | hold an actual QVariant. |
3015 | */ |
3016 | |
3017 | /*! |
3018 | \fn template<typename Pointer> QVariantPointer<Pointer>::QVariantPointer(const Pointer *pointer) |
3019 | |
3020 | Constructs a QVariantPointer from the given \a pointer. |
3021 | */ |
3022 | |
3023 | /*! |
3024 | \fn template<typename Pointer> QVariantRef<Pointer> QVariantPointer<Pointer>::operator*() const |
3025 | |
3026 | Dereferences the QVariantPointer to a QVariantRef. |
3027 | */ |
3028 | |
3029 | /*! |
3030 | \fn template<typename Pointer> Pointer QVariantPointer<Pointer>::operator->() const |
3031 | |
3032 | Dereferences and returns the pointer. The pointer is expected to also |
3033 | implement operator->(). |
3034 | */ |
3035 | |
3036 | QT_END_NAMESPACE |
3037 |
Definitions
- qMetaTypeNumberBySize
- qMetaTypeNumber
- qMetaTypeUNumber
- qConvertToNumber
- qConvertToRealNumber
- isValidMetaTypeForVariant
- CustomConstructMoveOptions
- CustomConstructNullabilityOption
- customConstruct
- customClear
- clonePrivate
- create
- create
- ~QVariant
- QVariant
- QVariant
- prepareForEmplace
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- QVariant
- metaType
- operator=
- detach
- typeName
- clear
- mapIdFromQt3ToCurrent
- Qt5UserType
- Qt5LastCoreType
- Qt5FirstGuiType
- Qt5LastGuiType
- Qt5SizePolicy
- Qt5RegExp
- Qt5KeySequence
- Qt5QQuaternion
- Qt6ToQt5GuiTypeDelta
- load
- save
- operator>>
- operator<<
- toStringList
- toString
- toMap
- toHash
- toDate
- toTime
- toDateTime
- toEasingCurve
- toByteArray
- toPoint
- toRect
- toSize
- toSizeF
- toRectF
- toLineF
- toLine
- toPointF
- toUrl
- toLocale
- toRegularExpression
- toModelIndex
- toPersistentModelIndex
- toUuid
- toJsonValue
- toJsonObject
- toJsonArray
- toJsonDocument
- toChar
- toBitArray
- qNumVariantToHelper
- toInt
- toUInt
- toLongLong
- toULongLong
- toBool
- toDouble
- toFloat
- toReal
- toList
- convert
- convert
- view
- qIsNumericType
- qIsFloatingPoint
- canBeNumericallyCompared
- numericTypePromotion
- spaceShip
- integralCompare
- numericCompare
- qvCanConvertMetaObject
- pointerCompare
- equals
- compare
- data
- isNull
- qdebugHelper
- moveConstruct
- copyConstruct
- operator<<
- fromMetaType
- convert
- coerce
- QVariantConstPointer
- operator*
Learn to use CMake with our Intro Training
Find out more