\inmodule QtCore More...

#include <qmetacontainer.h>

Inheritance diagram for QMetaAssociation:

Collaboration diagram for QMetaAssociation:

Public Types
using	Iterable = QtMetaContainerPrivate::Association

Public Member Functions
	QMetaAssociation ()=default
	QMetaAssociation (const QtMetaContainerPrivate::QMetaAssociationInterface *d)
QMetaType	keyMetaType () const
	Returns the meta type for keys in the container.
QMetaType	mappedMetaType () const
	Returns the meta type for mapped values in the container.
bool	canInsertKey () const
	Returns `true` if keys can be added to the container using \l insertKey(), otherwise returns `false`.
void	insertKey (void container, const void key) const
	Inserts the key into the container if possible.
bool	canRemoveKey () const
	Returns `true` if keys can be removed from the container using \l removeKey(), otherwise returns `false`.
void	removeKey (void container, const void key) const
	Removes the key and its associated mapped value from the container if possible.
bool	canContainsKey () const
	Returns `true` if the container can be queried for keys using \l containsKey(), otherwise returns `false`.
bool	containsKey (const void container, const void key) const
	Returns `true` if the container can be queried for keys and contains the key, otherwise returns `false`.
bool	canGetMappedAtKey () const
	Returns `true` if the container can be queried for values using \l mappedAtKey(), otherwise returns `false`.
void	mappedAtKey (const void container, const void key, void *mapped) const
	Retrieves the mapped value associated with the key in the container and places it in the memory location pointed to by mapped, if that is possible.
bool	canSetMappedAtKey () const
	Returns `true` if mapped values can be modified in the container using \l setMappedAtKey(), otherwise returns `false`.
void	setMappedAtKey (void container, const void key, const void *mapped) const
	Overwrites the value associated with the key in the container using the mapped value passed as argument if that is possible.
bool	canGetKeyAtIterator () const
	Returns `true` if a key can be retrieved from a non-const iterator using \l keyAtIterator(), otherwise returns `false`.
void	keyAtIterator (const void iterator, void key) const
	Retrieves the key pointed to by the non-const iterator and stores it in the memory location pointed to by key, if possible.
bool	canGetKeyAtConstIterator () const
	Returns `true` if a key can be retrieved from a const iterator using \l keyAtConstIterator(), otherwise returns `false`.
void	keyAtConstIterator (const void iterator, void key) const
	Retrieves the key pointed to by the const iterator and stores it in the memory location pointed to by key, if possible.
bool	canGetMappedAtIterator () const
	Returns `true` if a mapped value can be retrieved from a non-const iterator using \l mappedAtIterator(), otherwise returns `false`.
void	mappedAtIterator (const void iterator, void mapped) const
	Retrieves the mapped value pointed to by the non-const iterator and stores it in the memory location pointed to by mapped, if possible.
bool	canGetMappedAtConstIterator () const
	Returns `true` if a mapped value can be retrieved from a const iterator using \l mappedAtConstIterator(), otherwise returns `false`.
void	mappedAtConstIterator (const void iterator, void mapped) const
	Retrieves the mapped value pointed to by the const iterator and stores it in the memory location pointed to by mapped, if possible.
bool	canSetMappedAtIterator () const
	Returns `true` if a mapped value can be set via a non-const iterator using \l setMappedAtIterator(), otherwise returns `false`.
void	setMappedAtIterator (const void iterator, const void mapped) const
	Writes the mapped value to the container location pointed to by the non-const iterator, if possible.
bool	canCreateIteratorAtKey () const
	Returns `true` if an iterator pointing to an entry in the container can be created using \l createIteratorAtKey(), otherwise returns false.
void *	createIteratorAtKey (void container, const void key) const
	Returns a non-const iterator pointing to the entry of key in the container, if possible.
bool	canCreateConstIteratorAtKey () const
	Returns `true` if a const iterator pointing to an entry in the container can be created using \l createConstIteratorAtKey(), otherwise returns false.
void *	createConstIteratorAtKey (const void container, const void key) const
	Returns a const iterator pointing to the entry of key in the container, if possible.
const QtMetaContainerPrivate::QMetaAssociationInterface *	iface () const
Public Member Functions inherited from QMetaContainer
	QMetaContainer ()=default
	QMetaContainer (const QtMetaContainerPrivate::QMetaContainerInterface *d)
bool	hasInputIterator () const
	Returns `true` if the underlying container provides at least an input iterator as defined by std::input_iterator_tag, otherwise returns `false`.
bool	hasForwardIterator () const
	Returns `true` if the underlying container provides at least a forward iterator as defined by std::forward_iterator_tag, otherwise returns `false`.
bool	hasBidirectionalIterator () const
	Returns `true` if the underlying container provides a bi-directional iterator or a random access iterator as defined by std::bidirectional_iterator_tag and std::random_access_iterator_tag, respectively.
bool	hasRandomAccessIterator () const
	Returns `true` if the underlying container provides a random access iterator as defined by std::random_access_iterator_tag, otherwise returns `false`.
bool	hasSize () const
	Returns `true` if the container can be queried for its size, `false` otherwise.
qsizetype	size (const void *container) const
	Returns the number of values in the given container if it can be queried for its size.
bool	canClear () const
	Returns `true` if the container can be cleared, `false` otherwise.
void	clear (void *container) const
	Clears the given container if it can be cleared.
bool	hasIterator () const
	Returns `true` if the underlying container offers a non-const iterator, `false` otherwise.
void *	begin (void *container) const
	Creates and returns a non-const iterator pointing to the beginning of container.
void *	end (void *container) const
	Creates and returns a non-const iterator pointing to the end of container.
void	destroyIterator (const void *iterator) const
	Destroys a non-const iterator previously created using \l begin() or \l end().
bool	compareIterator (const void i, const void j) const
	Returns `true` if the non-const iterators i and j point to the same value in the container they are iterating over, otherwise returns `false`.
void	copyIterator (void target, const void source) const
	Copies the non-const iterator source into the non-const iterator target.
void	advanceIterator (void *iterator, qsizetype step) const
	Advances the non-const iterator by step steps.
qsizetype	diffIterator (const void i, const void j) const
	Returns the distance between the non-const iterators i and j, the equivalent of i `-` j.
bool	hasConstIterator () const
	Returns `true` if the underlying container offers a const iterator, `false` otherwise.
void *	constBegin (const void *container) const
	Creates and returns a const iterator pointing to the beginning of container.
void *	constEnd (const void *container) const
	Creates and returns a const iterator pointing to the end of container.
void	destroyConstIterator (const void *iterator) const
	Destroys a const iterator previously created using \l constBegin() or \l constEnd().
bool	compareConstIterator (const void i, const void j) const
	Returns `true` if the const iterators i and j point to the same value in the container they are iterating over, otherwise returns `false`.
void	copyConstIterator (void target, const void source) const
	Copies the const iterator source into the const iterator target.
void	advanceConstIterator (void *iterator, qsizetype step) const
	Advances the const iterator by step steps.
qsizetype	diffConstIterator (const void i, const void j) const
	Returns the distance between the const iterators i and j, the equivalent of i `-` j.

Static Public Member Functions
template<typename T>
static constexpr QMetaAssociation	fromContainer ()

Friends
bool	comparesEqual (const QMetaAssociation &lhs, const QMetaAssociation &rhs) noexcept

Additional Inherited Members
Protected Attributes inherited from QMetaContainer
const QtMetaContainerPrivate::QMetaContainerInterface *	d_ptr = nullptr

Detailed Description

\inmodule QtCore

Since: 6.0

The QMetaAssociation class allows type erased access to associative containers.

\compares equality

The class provides a number of primitive container operations, using void* as operands. This way, you can manipulate a generic container retrieved from a Variant without knowing its type.

QMetaAssociation covers both, containers with mapped values such as QMap or QHash, and containers that only hold keys such as QSet.

The void* arguments to the various methods are typically created by using a \l QVariant of the respective container or value type, and calling its \l QVariant::data() or \l QVariant::constData() methods. However, you can also pass plain pointers to objects of the container or value type.

Iterator invalidation follows the rules given by the underlying containers and is not expressed in the API. Therefore, for a truly generic container, any iterators should be considered invalid after any write operation.

See also: QMetaContainer, QMetaSequence, QIterable, QIterator

Definition at line 1060 of file qmetacontainer.h.

Member Typedef Documentation

◆ Iterable

using QMetaAssociation::Iterable = QtMetaContainerPrivate::Association

Definition at line 1117 of file qmetacontainer.h.

Constructor & Destructor Documentation

◆ QMetaAssociation() [1/2]

QMetaAssociation::QMetaAssociation ( )

default

◆ QMetaAssociation() [2/2]

QMetaAssociation::QMetaAssociation ( const QtMetaContainerPrivate::QMetaAssociationInterface * d )

inlineexplicit

Definition at line 1121 of file qmetacontainer.h.

Member Function Documentation

◆ canContainsKey()

bool QMetaAssociation::canContainsKey ( ) const

inline

Returns true if the container can be queried for keys using \l containsKey(), otherwise returns false.

Definition at line 1156 of file qmetacontainer.h.

◆ canCreateConstIteratorAtKey()

bool QMetaAssociation::canCreateConstIteratorAtKey ( ) const

inline

Returns true if a const iterator pointing to an entry in the container can be created using \l createConstIteratorAtKey(), otherwise returns false.

Definition at line 1273 of file qmetacontainer.h.

◆ canCreateIteratorAtKey()

bool QMetaAssociation::canCreateIteratorAtKey ( ) const

inline

Returns true if an iterator pointing to an entry in the container can be created using \l createIteratorAtKey(), otherwise returns false.

See also: createIteratorAtKey()

Definition at line 1259 of file qmetacontainer.h.

◆ canGetKeyAtConstIterator()

bool QMetaAssociation::canGetKeyAtConstIterator ( ) const

inline

Returns true if a key can be retrieved from a const iterator using \l keyAtConstIterator(), otherwise returns false.

See also: keyAtConstIterator()

Definition at line 1207 of file qmetacontainer.h.

◆ canGetKeyAtIterator()

bool QMetaAssociation::canGetKeyAtIterator ( ) const

inline

Returns true if a key can be retrieved from a non-const iterator using \l keyAtIterator(), otherwise returns false.

See also: keyAtIterator()

Definition at line 1194 of file qmetacontainer.h.

◆ canGetMappedAtConstIterator()

bool QMetaAssociation::canGetMappedAtConstIterator ( ) const

inline

Returns true if a mapped value can be retrieved from a const iterator using \l mappedAtConstIterator(), otherwise returns false.

See also: mappedAtConstIterator()

Definition at line 1233 of file qmetacontainer.h.

◆ canGetMappedAtIterator()

bool QMetaAssociation::canGetMappedAtIterator ( ) const

inline

Returns true if a mapped value can be retrieved from a non-const iterator using \l mappedAtIterator(), otherwise returns false.

See also: mappedAtIterator()

Definition at line 1220 of file qmetacontainer.h.

◆ canGetMappedAtKey()

bool QMetaAssociation::canGetMappedAtKey ( ) const

inline

Returns true if the container can be queried for values using \l mappedAtKey(), otherwise returns false.

Definition at line 1170 of file qmetacontainer.h.

◆ canInsertKey()

bool QMetaAssociation::canInsertKey ( ) const

inline

Returns true if keys can be added to the container using \l insertKey(), otherwise returns false.

See also: insertKey()

Definition at line 1132 of file qmetacontainer.h.

◆ canRemoveKey()

bool QMetaAssociation::canRemoveKey ( ) const

inline

Returns true if keys can be removed from the container using \l removeKey(), otherwise returns false.

See also: removeKey()

Definition at line 1144 of file qmetacontainer.h.

◆ canSetMappedAtIterator()

bool QMetaAssociation::canSetMappedAtIterator ( ) const

inline

Returns true if a mapped value can be set via a non-const iterator using \l setMappedAtIterator(), otherwise returns false.

See also: setMappedAtIterator()

Definition at line 1246 of file qmetacontainer.h.

◆ canSetMappedAtKey()

bool QMetaAssociation::canSetMappedAtKey ( ) const

inline

Returns true if mapped values can be modified in the container using \l setMappedAtKey(), otherwise returns false.

See also: setMappedAtKey()

Definition at line 1182 of file qmetacontainer.h.

◆ containsKey()

bool QMetaAssociation::containsKey	(	const void *	container,
		const void *	key ) const

inline

Returns true if the container can be queried for keys and contains the key, otherwise returns false.

See also: canContainsKey()

Definition at line 1162 of file qmetacontainer.h.

◆ createConstIteratorAtKey()

void * QMetaAssociation::createConstIteratorAtKey	(	const void *	container,
		const void *	key ) const

inline

Returns a const iterator pointing to the entry of key in the container, if possible.

If the entry doesn't exist, creates a const iterator pointing to the end of the container. If no const iterator can be created, returns nullptr.

The const iterator has to be destroyed using destroyConstIterator().

See also: canCreateConstIteratorAtKey(), constBegin(), constEnd(), destroyConstIterator()

Definition at line 1280 of file qmetacontainer.h.

◆ createIteratorAtKey()

void * QMetaAssociation::createIteratorAtKey	(	void *	container,
		const void *	key ) const

inline

Returns a non-const iterator pointing to the entry of key in the container, if possible.

If the entry doesn't exist, creates a non-const iterator pointing to the end of the container. If no non-const iterator can be created, returns nullptr.

The non-const iterator has to be destroyed using destroyIterator().

See also: canCreateIteratorAtKey(), begin(), end(), destroyIterator()

Definition at line 1266 of file qmetacontainer.h.

◆ fromContainer()

template<typename T>

constexpr QMetaAssociation QMetaAssociation::fromContainer ( )

inlinestaticconstexpr

Since: 6.0

Returns the QMetaAssociation corresponding to the type given as template parameter.

Definition at line 1124 of file qmetacontainer.h.

◆ iface()

const QtMetaContainerPrivate::QMetaAssociationInterface * QMetaAssociation::iface ( ) const

inline

Definition at line 1287 of file qmetacontainer.h.

◆ insertKey()

void QMetaAssociation::insertKey	(	void *	container,
		const void *	key ) const

inline

Inserts the key into the container if possible.

If the container has mapped values a default-create mapped value is associated with the key.

See also: canInsertKey()

Definition at line 1138 of file qmetacontainer.h.

◆ keyAtConstIterator()

void QMetaAssociation::keyAtConstIterator	(	const void *	iterator,
		void *	key ) const

inline

Retrieves the key pointed to by the const iterator and stores it in the memory location pointed to by key, if possible.

See also: canGetKeyAtConstIterator(), constBegin(), constEnd(), createConstIteratorAtKey()

Definition at line 1214 of file qmetacontainer.h.

◆ keyAtIterator()

void QMetaAssociation::keyAtIterator	(	const void *	iterator,
		void *	key ) const

inline

Retrieves the key pointed to by the non-const iterator and stores it in the memory location pointed to by key, if possible.

See also: canGetKeyAtIterator(), begin(), end(), createIteratorAtKey()

Definition at line 1201 of file qmetacontainer.h.

◆ keyMetaType()

QMetaType QMetaAssociation::keyMetaType ( ) const

Returns the meta type for keys in the container.

Definition at line 49 of file qmetaassociation.cpp.

◆ mappedAtConstIterator()

void QMetaAssociation::mappedAtConstIterator	(	const void *	iterator,
		void *	mapped ) const

inline

Retrieves the mapped value pointed to by the const iterator and stores it in the memory location pointed to by mapped, if possible.

See also: canGetMappedAtConstIterator(), constBegin(), constEnd(), createConstIteratorAtKey()

Definition at line 1240 of file qmetacontainer.h.

◆ mappedAtIterator()

void QMetaAssociation::mappedAtIterator	(	const void *	iterator,
		void *	mapped ) const

inline

Retrieves the mapped value pointed to by the non-const iterator and stores it in the memory location pointed to by mapped, if possible.

See also: canGetMappedAtIterator(), begin(), end(), createIteratorAtKey()

Definition at line 1227 of file qmetacontainer.h.

◆ mappedAtKey()

void QMetaAssociation::mappedAtKey	(	const void *	container,
		const void *	key,
		void *	mapped ) const

inline

Retrieves the mapped value associated with the key in the container and places it in the memory location pointed to by mapped, if that is possible.

See also: canGetMappedAtKey()

Definition at line 1176 of file qmetacontainer.h.

◆ mappedMetaType()

QMetaType QMetaAssociation::mappedMetaType ( ) const

Returns the meta type for mapped values in the container.

Definition at line 59 of file qmetaassociation.cpp.

◆ removeKey()

void QMetaAssociation::removeKey	(	void *	container,
		const void *	key ) const

inline

Removes the key and its associated mapped value from the container if possible.

See also: canRemoveKey()

Definition at line 1150 of file qmetacontainer.h.

◆ setMappedAtIterator()

void QMetaAssociation::setMappedAtIterator	(	const void *	iterator,
		const void *	mapped ) const

inline

Writes the mapped value to the container location pointed to by the non-const iterator, if possible.

See also: canSetMappedAtIterator(), begin(), end(), createIteratorAtKey()

Definition at line 1253 of file qmetacontainer.h.

◆ setMappedAtKey()

void QMetaAssociation::setMappedAtKey	(	void *	container,
		const void *	key,
		const void *	mapped ) const

inline

Overwrites the value associated with the key in the container using the mapped value passed as argument if that is possible.

See also: canSetMappedAtKey()

Definition at line 1188 of file qmetacontainer.h.

◆ comparesEqual

bool comparesEqual	(	const QMetaAssociation &	lhs,
		const QMetaAssociation &	rhs )

friend

Definition at line 1290 of file qmetacontainer.h.

The documentation for this class was generated from the following files:

qtbase/src/corelib/kernel/qmetacontainer.h (bc83d91d4e3575ba688d65e12860c05b3fb1dcbd)
qtbase/src/corelib/kernel/qmetaassociation.cpp (bc83d91d4e3575ba688d65e12860c05b3fb1dcbd)

Public Types

Public Member Functions

Static Public Member Functions

Friends

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ Iterable

Constructor & Destructor Documentation

◆ QMetaAssociation() [1/2]

◆ QMetaAssociation() [2/2]

Member Function Documentation

◆ canContainsKey()

◆ canCreateConstIteratorAtKey()

◆ canCreateIteratorAtKey()

◆ canGetKeyAtConstIterator()

◆ canGetKeyAtIterator()

◆ canGetMappedAtConstIterator()

◆ canGetMappedAtIterator()

◆ canGetMappedAtKey()

◆ canInsertKey()

◆ canRemoveKey()

◆ canSetMappedAtIterator()

◆ canSetMappedAtKey()

◆ containsKey()

◆ createConstIteratorAtKey()

◆ createIteratorAtKey()

◆ fromContainer()

◆ iface()

◆ insertKey()

◆ keyAtConstIterator()

◆ keyAtIterator()

◆ keyMetaType()

◆ mappedAtConstIterator()

◆ mappedAtIterator()

◆ mappedAtKey()

◆ mappedMetaType()

◆ removeKey()

◆ setMappedAtIterator()

◆ setMappedAtKey()

Friends And Related Symbol Documentation

◆ comparesEqual