QTaggedIterator Class
template <typename Iterator, typename IteratorCategory> class QTaggedIteratorQTaggedIterator is a template class that wraps an iterator and exposes standard iterator traits. More...
Header: | #include <QTaggedIterator> |
CMake: | find_package(Qt6 COMPONENTS Core REQUIRED) target_link_libraries(mytarget PRIVATE Qt6::Core) |
qmake: | QT += core |
Since: | Qt 6.0 |
Public Functions
QTaggedIterator(Iterator &&it) | |
bool | operator!=(const QTaggedIterator<Iterator, IteratorCategory> &other) const |
QTaggedIterator<Iterator, IteratorCategory> | operator+(qsizetype j) const |
QTaggedIterator<Iterator, IteratorCategory> & | operator++() |
QTaggedIterator<Iterator, IteratorCategory> | operator++(int x) |
QTaggedIterator<Iterator, IteratorCategory> & | operator+=(qsizetype j) |
QTaggedIterator<Iterator, IteratorCategory> | operator-(qsizetype j) const |
qsizetype | operator-(const QTaggedIterator<Iterator, IteratorCategory> &j) const |
QTaggedIterator<Iterator, IteratorCategory> & | operator--() |
QTaggedIterator<Iterator, IteratorCategory> | operator--(int x) |
QTaggedIterator<Iterator, IteratorCategory> & | operator-=(qsizetype j) |
bool | operator==(const QTaggedIterator<Iterator, IteratorCategory> &other) const |
Related Non-Members
QTaggedIterator<Iterator, IteratorCategory> | operator+(qsizetype j, const QTaggedIterator<Iterator, IteratorCategory> &k) |
Detailed Description
In order to use an iterator any of the standard algorithms, its iterator traits need to be known. As QSequentialIterable can work with many different kinds of containers, we cannot declare the traits in the iterator classes themselves. A QTaggedIterator gives you a way to explicitly declare a trait for a concrete instance of an iterator or QConstIterator.
Member Function Documentation
QTaggedIterator::QTaggedIterator(Iterator &&it)
Constructs a QTaggedIterator from an iterator or QConstIterator it. Checks whether the IteratorCategory passed as template argument matches the run time capabilities of it; if there's no match, it is refused.
bool QTaggedIterator::operator!=(const QTaggedIterator<Iterator, IteratorCategory> &other) const
Returns true
if other points to a different item than this iterator; otherwise returns false
.
See also operator==().
QTaggedIterator<Iterator, IteratorCategory> QTaggedIterator::operator+(qsizetype j) const
Returns an iterator to the item at j positions forward from this iterator.
See also operator-() and operator+=().
QTaggedIterator<Iterator, IteratorCategory> &QTaggedIterator::operator++()
The prefix ++ operator (++it
) advances the iterator to the next item in the container and returns an iterator to the new current item.
Calling this function on QSequentialIterable::end() leads to undefined results.
See also operator--().
QTaggedIterator<Iterator, IteratorCategory> QTaggedIterator::operator++(int x)
This is an overloaded function.
The postfix ++ operator (it++
) advances the iterator to the next item in the container and returns an iterator to the previously current item.
QTaggedIterator<Iterator, IteratorCategory> &QTaggedIterator::operator+=(qsizetype j)
Advances the iterator by j items.
See also operator-=() and operator+().
QTaggedIterator<Iterator, IteratorCategory> QTaggedIterator::operator-(qsizetype j) const
Returns an iterator to the item at j positions backward from this iterator.
If the container in the QVariant does not support bi-directional iteration, calling this function leads to undefined results.
See also operator+(), operator-=(), and QIterable::canReverseIterate().
qsizetype QTaggedIterator::operator-(const QTaggedIterator<Iterator, IteratorCategory> &j) const
Returns the distance between this iterator and j.
See also operator+(), operator-=(), and QIterable::canReverseIterate().
QTaggedIterator<Iterator, IteratorCategory> &QTaggedIterator::operator--()
The prefix -- operator (--it
) makes the preceding item current and returns an iterator to the new current item.
Calling this function on QSequentialIterable::begin() leads to undefined results.
If the container in the QVariant does not support bi-directional iteration, calling this function leads to undefined results.
See also operator++() and QIterable::canReverseIterate().
QTaggedIterator<Iterator, IteratorCategory> QTaggedIterator::operator--(int x)
This is an overloaded function.
The postfix -- operator (it--
) makes the preceding item current and returns an iterator to the previously current item.
If the container in the QVariant does not support bi-directional iteration, calling this function leads to undefined results.
See also QIterable::canReverseIterate().
QTaggedIterator<Iterator, IteratorCategory> &QTaggedIterator::operator-=(qsizetype j)
Makes the iterator go back by j items.
If the container in the QVariant does not support bi-directional iteration, calling this function leads to undefined results.
See also operator+=(), operator-(), and QIterable::canReverseIterate().
bool QTaggedIterator::operator==(const QTaggedIterator<Iterator, IteratorCategory> &other) const
Returns true
if other points to the same item as this iterator; otherwise returns false
.
See also operator!=().
Related Non-Members
QTaggedIterator<Iterator, IteratorCategory> operator+(qsizetype j, const QTaggedIterator<Iterator, IteratorCategory> &k)
Returns an iterator to the item at j positions forward from iterator k.
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