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[править] QQueue Class Reference
^{[модуль QtCore ]}

The QQueue class is a generic container that provides a queue. Далее...

 #include <QQueue>

Inherits QList<T>.

Примечание: все функции в этом классе реентерабельны.

• Список всех членов, включая унаследованные

[править] Открытые функции

• QQueue ()
• ~QQueue ()
• T dequeue ()
• void enqueue ( const T & t )
• T & head ()
• const T & head () const

• 60 public functions inherited from QList

[править] Дополнительные унаследованные члены

• 3 static public members inherited from QList

[править] Подробное описание

The QQueue class is a generic container that provides a queue.

QQueue<T> is one of Qt's generic container classes. It implements a queue data structure for items of a same type.

A queue is a first in, first out (FIFO) structure. Items are added to the tail of the queue using enqueue() and retrieved from the head using dequeue(). The head() function provides access to the head item without removing it.

Пример:

 QQueue<int> queue;
 queue.enqueue(1);
 queue.enqueue(2);
 queue.enqueue(3);
 while (!queue.isEmpty())
     cout << queue.dequeue() << endl;

The example will output 1, 2, 3 in that order.

QQueue inherits from QList. All of QList's functionality also applies to QQueue. For example, you can use isEmpty() to test whether the queue is empty, and you can traverse a QQueue using QList's iterator classes (for example, QListIterator). But in addition, QQueue provides three convenience functions that make it easy to implement FIFO semantics: enqueue(), dequeue(), and head().

QQueue's value type must be an assignable data type. This covers most data types that are commonly used, but the compiler won't let you, for example, store a QWidget as a value; instead, store a QWidget *.

See also QList and QStack.

[править] Описание функций-членов

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QQueue::QQueue ()

Constructs an empty queue.

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QQueue::~QQueue ()

Destroys the queue. References to the values in the queue, and all iterators over this queue, become invalid.

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T QQueue::dequeue ()

Removes the head item in the queue and returns it. This function assumes that the queue isn't empty.

This is the same as QList::takeFirst().

See also head(), enqueue(), and isEmpty().

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void QQueue::enqueue ( const T & t )

Adds value t to the tail of the queue.

This is the same as QList::append().

See also dequeue() and head().

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T & QQueue::head ()

Returns a reference to the queue's head item. This function assumes that the queue isn't empty.

This is the same as QList::first().

See also dequeue(), enqueue(), and isEmpty().

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const T & QQueue::head () const

Эта перегруженная функция предоставлена для удобства.