ConstIterator Class

Class ConstIterator is declared in class QCborMap.

The QCborMap::ConstIterator class provides an STL-style const iterator for QCborMap. More...

This class was introduced in Qt 5.12.

Public Types

Public Functions

ConstIterator(const ConstIterator &other)
ConstIterator()
ConstIterator &operator=(const ConstIterator &other)
QCborValue key() const
QCborValueRef value() const
bool operator!=(const Iterator &other) const
bool operator!=(const ConstIterator &other) const
ConstIterator::value_type operator*() const
ConstIterator operator+(qsizetype j) const
ConstIterator &operator++()
ConstIterator operator++(int)
ConstIterator &operator+=(qsizetype j)
ConstIterator operator-(qsizetype j) const
qsizetype operator-(ConstIterator j) const
ConstIterator &operator--()
ConstIterator operator--(int)
ConstIterator &operator-=(qsizetype j)
const QCborValueRef *operator->() const
bool operator<(const Iterator &other) const
bool operator<(const ConstIterator &other) const
bool operator<=(const Iterator &other) const
bool operator<=(const ConstIterator &other) const
bool operator==(const Iterator &other) const
bool operator==(const ConstIterator &other) const
bool operator>(const Iterator &other) const
bool operator>(const ConstIterator &other) const
bool operator>=(const Iterator &other) const
bool operator>=(const ConstIterator &other) const

Detailed Description

QCborMap::ConstIterator allows you to iterate over a QCborMap. If you want to modify the QCborMap as you iterate over it, you must use QCborMap::Iterator instead. It is generally good practice to use QCborMap::ConstIterator, even on a non-const QCborMap, when you don't need to change the QCborMap through the iterator. Const iterators are slightly faster and improve code readability.

You must initialize the iterator using a QCborMap function like QCborMap::begin(), QCborMap::end(), or QCborMap::find() before you can start iterating..

Multiple iterators can be used on the same object. Existing iterators will however become dangling if the object gets modified.

See also QCborMap::Iterator.

Member Type Documentation

typedef ConstIterator::iterator_category

A synonym for std::random_access_iterator_tag indicating this iterator is a random-access iterator.

Member Function Documentation

ConstIterator::ConstIterator(const ConstIterator &other)

Constructs an iterator as a copy of other.

ConstIterator::ConstIterator()

Constructs an uninitialized iterator.

Functions like key(), value(), and operator++() must not be called on an uninitialized iterator. Use operator=() to assign a value to it before using it.

See also QCborMap::constBegin() and QCborMap::constEnd().

ConstIterator &ConstIterator::operator=(const ConstIterator &other)

Makes this iterator a copy of other and returns a reference to this iterator.

QCborValue ConstIterator::key() const

Returns the current item's key.

See also value().

QCborValueRef ConstIterator::value() const

Returns the current item's value.

See also key() and operator*().

ConstIterator::value_type ConstIterator::operator*() const

Returns a pair containing the curent item's key and value.

See also key() and value().

ConstIterator ConstIterator::operator+(qsizetype j) const

Returns an iterator to the item at j positions forward from this iterator. If j is negative, the iterator goes backward.

See also operator-().

ConstIterator &ConstIterator::operator++()

The prefix ++ operator, ++i, advances the iterator to the next item in the map and returns this iterator.

Calling this function on QCborMap::end() leads to undefined results.

See also operator--().

ConstIterator ConstIterator::operator++(int)

This is an overloaded function.

The postfix ++ operator, i++, advances the iterator to the next item in the map and returns an iterator to the previously current item.

ConstIterator &ConstIterator::operator+=(qsizetype j)

Advances the iterator by j items. If j is negative, the iterator goes backward. Returns a reference to this iterator.

See also operator-=() and operator+().

ConstIterator ConstIterator::operator-(qsizetype j) const

Returns an iterator to the item at j positions backward from this iterator. If j is negative, the iterator goes forward.

See also operator+().

qsizetype ConstIterator::operator-(ConstIterator j) const

Returns the position of the item at iterator j relative to the item at this iterator. If the item at j is forward of this time, the returned value is negative.

See also operator+().

ConstIterator &ConstIterator::operator--()

The prefix -- operator, --i, makes the preceding item current and returns this iterator.

Calling this function on QCborMap::begin() leads to undefined results.

See also operator++().

ConstIterator ConstIterator::operator--(int)

This is an overloaded function.

The postfix -- operator, i--, makes the preceding item current and returns an iterator pointing to the previously current item.

ConstIterator &ConstIterator::operator-=(qsizetype j)

Makes the iterator go back by j items. If j is negative, the iterator goes forward. Returns a reference to this iterator.

See also operator+=() and operator-().

const QCborValueRef *ConstIterator::operator->() const

Returns a pointer to the current pair's value.

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