const_iterator Class▲
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Header: const_iterator
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Since: Qt 4.4
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qmake: QT += core
Detailed Description▲
QFuture provides both STL-style iterators and Java-style iterators. The STL-style iterators are more low-level and more cumbersome to use; on the other hand, they are slightly faster and, for developers who already know STL, have the advantage of familiarity.
The default QFuture::const_iterator constructor creates an uninitialized iterator. You must initialize it using a QFuture function like QFuture::constBegin() or QFuture::constEnd() before you start iterating. Here's a typical loop that prints all the results available in a future:
QFuture<QString> future = ...;
QFuture<QString>::const_iterator i;
for (i = future.constBegin(); i != future.constEnd(); ++i)
cout << *i << endl;See Also▲
See also QFutureIterator, QFuture
Member Type Documentation▲
const_iterator::difference_type▲
Typedef for ptrdiff_t. Provided for STL compatibility.
const_iterator::iterator_category▲
Typedef for std::bidirectional_iterator_tag. Provided for STL compatibility.
const_iterator::pointer▲
Typedef for const T *. Provided for STL compatibility.
const_iterator::reference▲
Typedef for const T &. Provided for STL compatibility.
const_iterator::value_type▲
Typedef for T. Provided for STL compatibility.
Member Function Documentation▲
const_iterator::const_iterator()▲
Constructs an uninitialized iterator.
Functions like operator*() and operator++() should not be called on an uninitialized iterartor. Use operator=() to assign a value to it before using it.
See Also▲
See also QFuture::constBegin(), QFuture::constEnd()
const_iterator::const_iterator(const const_iterator &other)▲
Constructs a copy of other.
bool const_iterator::operator!=(const const_iterator &other) const▲
Returns true if other points to a different result than this iterator; otherwise returns false.
See Also▲
See also operator==()
const T &const_iterator::operator*() const▲
Returns the current result.
const_iterator const_iterator::operator+(int j) const▲
Returns an iterator to the results at j positions forward from this iterator. (If j is negative, the iterator goes backward.)
See Also▲
See also operator-(), operator+=()
const_iterator &const_iterator::operator++()▲
The prefix ++ operator (++it) advances the iterator to the next result in the future and returns an iterator to the new current result.
Calling this function on QFuture<T>::constEnd() leads to undefined results.
See Also▲
See also operator--()
const_iterator const_iterator::operator++(int)▲
This is an overloaded function.
The postfix ++ operator (it++) advances the iterator to the next result in the future and returns an iterator to the previously current result.
const_iterator &const_iterator::operator+=(int j)▲
Advances the iterator by j results. (If j is negative, the iterator goes backward.)
See Also▲
See also operator-=(), operator+()
const_iterator const_iterator::operator-(int j) const▲
Returns an iterator to the result at j positions backward from this iterator. (If j is negative, the iterator goes forward.)
See Also▲
See also operator+(), operator-=()
const_iterator &const_iterator::operator--()▲
The prefix – operator (--it) makes the preceding result current and returns an iterator to the new current result.
Calling this function on QFuture<T>::constBegin() leads to undefined results.
See Also▲
See also operator++()
const_iterator const_iterator::operator--(int)▲
This is an overloaded function.
The postfix – operator (it--) makes the preceding result current and returns an iterator to the previously current result.
const_iterator &const_iterator::operator-=(int j)▲
Makes the iterator go back by j results. (If j is negative, the iterator goes forward.)
See Also▲
See also operator+=(), operator-()
const T *const_iterator::operator->() const▲
Returns a pointer to the current result.
const_iterator &const_iterator::operator=(const const_iterator &other)▲
Assigns other to this iterator.
bool const_iterator::operator==(const const_iterator &other) const▲
Returns true if other points to the same result as this iterator; otherwise returns false.
See Also▲
See also operator!=()