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// Copyright (C) 2020 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include <QtCore/qsequentialiterable.h>
#include <QtCore/qvariant.h>
#include <QtCore/private/qiterable_p.h>
QT_BEGIN_NAMESPACE
/*!
\class QSequentialIterable
\since 5.2
\inmodule QtCore
\brief The QSequentialIterable class is an iterable interface for a container in a QVariant.
This class allows several methods of accessing the values of a container held within
a QVariant. An instance of QSequentialIterable can be extracted from a QVariant if it can
be converted to a QVariantList.
\snippet code/src_corelib_kernel_qvariant.cpp 9
The container itself is not copied before iterating over it.
\sa QVariant
*/
/*!
\typedef QSequentialIterable::RandomAccessIterator
Exposes an iterator using std::random_access_iterator_tag.
*/
/*!
\typedef QSequentialIterable::BidirectionalIterator
Exposes an iterator using std::bidirectional_iterator_tag.
*/
/*!
\typedef QSequentialIterable::ForwardIterator
Exposes an iterator using std::forward_iterator_tag.
*/
/*!
\typedef QSequentialIterable::InputIterator
Exposes an iterator using std::input_iterator_tag.
*/
/*!
\typedef QSequentialIterable::RandomAccessConstIterator
Exposes a const_iterator using std::random_access_iterator_tag.
*/
/*!
\typedef QSequentialIterable::BidirectionalConstIterator
Exposes a const_iterator using std::bidirectional_iterator_tag.
*/
/*!
\typedef QSequentialIterable::ForwardConstIterator
Exposes a const_iterator using std::forward_iterator_tag.
*/
/*!
\typedef QSequentialIterable::InputConstIterator
Exposes a const_iterator using std::input_iterator_tag.
*/
/*!
Adds \a value to the container, at \a position, if possible.
*/
void QSequentialIterable::addValue(const QVariant &value, Position position)
{
QtPrivate::QVariantTypeCoercer coercer;
const void *valuePtr = coercer.coerce(value, metaContainer().valueMetaType());
switch (position) {
case AtBegin:
if (metaContainer().canAddValueAtBegin())
metaContainer().addValueAtBegin(mutableIterable(), valuePtr);
break;
case AtEnd:
if (metaContainer().canAddValueAtEnd())
metaContainer().addValueAtEnd(mutableIterable(), valuePtr);
break;
case Unspecified:
if (metaContainer().canAddValue())
metaContainer().addValue(mutableIterable(), valuePtr);
break;
}
}
/*!
Removes a value from the container, at \a position, if possible.
*/
void QSequentialIterable::removeValue(Position position)
{
switch (position) {
case AtBegin:
if (metaContainer().canRemoveValueAtBegin())
metaContainer().removeValueAtBegin(mutableIterable());
break;
case AtEnd:
if (metaContainer().canRemoveValueAtEnd())
metaContainer().removeValueAtEnd(mutableIterable());
break;
case Unspecified:
if (metaContainer().canRemoveValue())
metaContainer().removeValue(mutableIterable());
break;
}
}
QMetaType QSequentialIterable::valueMetaType() const
{
return QMetaType(metaContainer().valueMetaType());
}
/*!
Returns the value at position \a idx in the container.
*/
QVariant QSequentialIterable::at(qsizetype idx) const
{
QVariant v(valueMetaType());
void *dataPtr;
if (valueMetaType() == QMetaType::fromType<QVariant>())
dataPtr = &v;
else
dataPtr = v.data();
const QMetaSequence meta = metaContainer();
if (meta.canGetValueAtIndex()) {
meta.valueAtIndex(m_iterable.constPointer(), idx, dataPtr);
} else if (meta.canGetValueAtConstIterator()) {
void *iterator = meta.constBegin(m_iterable.constPointer());
meta.advanceConstIterator(iterator, idx);
meta.valueAtConstIterator(iterator, dataPtr);
meta.destroyConstIterator(iterator);
}
return v;
}
/*!
Sets the element at position \a idx in the container to \a value.
*/
void QSequentialIterable::set(qsizetype idx, const QVariant &value)
{
QtPrivate::QVariantTypeCoercer coercer;
const void *dataPtr = coercer.coerce(value, metaContainer().valueMetaType());
const QMetaSequence meta = metaContainer();
if (meta.canSetValueAtIndex()) {
meta.setValueAtIndex(m_iterable.mutablePointer(), idx, dataPtr);
} else if (meta.canSetValueAtIterator()) {
void *iterator = meta.begin(m_iterable.mutablePointer());
meta.advanceIterator(iterator, idx);
meta.setValueAtIterator(iterator, dataPtr);
meta.destroyIterator(iterator);
}
}
/*!
\typealias QSequentialIterable::const_iterator
\brief The QSequentialIterable::const_iterator allows iteration over a container in a QVariant.
A QSequentialIterable::const_iterator can only be created by a QSequentialIterable instance,
and can be used in a way similar to other stl-style iterators.
\snippet code/src_corelib_kernel_qvariant.cpp 9
*/
/*!
\typealias QSequentialIterable::iterator
\since 6.0
\brief The QSequentialIterable::iterator allows iteration over a container in a QVariant.
A QSequentialIterable::iterator can only be created by a QSequentialIterable instance,
and can be used in a way similar to other stl-style iterators.
*/
/*!
Returns the current item, converted to a QVariantRef.
*/
QVariantRef<QSequentialIterator> QSequentialIterator::operator*() const
{
return QVariantRef<QSequentialIterator>(this);
}
/*!
Returns the current item, converted to a QVariantPointer.
*/
QVariantPointer<QSequentialIterator> QSequentialIterator::operator->() const
{
return QVariantPointer<QSequentialIterator>(this);
}
/*!
Returns the current item, converted to a QVariant.
*/
QVariant QSequentialConstIterator::operator*() const
{
return QIterablePrivate::retrieveElement(metaContainer().valueMetaType(), [this](void *dataPtr) {
metaContainer().valueAtConstIterator(constIterator(), dataPtr);
});
}
/*!
Returns the current item, converted to a QVariantConstPointer.
*/
QVariantConstPointer QSequentialConstIterator::operator->() const
{
return QVariantConstPointer(operator*());
}
QT_END_NAMESPACE
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