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/*!

    \class QQueue

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

    \ingroup tools

    \ingroup shared

    \reentrant

    QQueue\<T\> is one of Qt's generic \l{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.

    Example:

    \snippet doc/src/snippets/code/src_corelib_tools_qqueue.cpp 0

    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 \l{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. Use

    QWidget* instead.

    \sa QList, QStack

*/

/*!

    \fn QQueue::QQueue()

    Constructs an empty queue.

*/

/*!

    \fn QQueue::~QQueue()

    Destroys the queue. References to the values in the queue, and all

    iterators over this queue, become invalid.

*/

/*!

    \fn void QQueue::enqueue(const T& t)

    Adds value \a t to the tail of the queue.

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

    \sa dequeue(), head()

*/

/*!

    \fn 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().

    \sa dequeue(), enqueue(), isEmpty()

*/

/*!

    \fn const T &QQueue::head() const

    \overload

*/

/*!

    \fn 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().

    \sa head(), enqueue(), isEmpty()

*/