Queue

It offers the opposite functionality of a stack which follows the 'last-in, first-out' policy.

'first-in, first-out' means that the first value that has been enqueued/added to the queue is the first that gets dequeued/removed.

The usage of a queue is quite simple. You have one method to add/enqueue values enqueue and one method to remove/dequeue them dequeue. You can also peek at the beginning of the queue to see what value has been added/enqueued at first without removing it peek.

If you want to iterate over the values of the queue you can either use the iterator returned by the iterator method or the array that contains the queue's values returned by the toArray method.

The two methods isEmpty and size let you find out whether the queue contains values and how many values it contains.

Example:

// the queue gets set up
var queue:Queue = new MyQueue();
queue.enqueue("value1");
queue.enqueue("value2");
queue.enqueue("value3");
// the queue gets used somewhere in your application
trace(queue.peek()); // traces the first element without removing it
while (!queue.isEmpty()) {
    trace(queue.dequeue());
}

Output:

value1
value1
value2
value3