Class QUEUE

Method QUEUE:EMPTY()

 Empty() --> TRUE || FALSE

Empty() returns TRUE if queue is empty and FALSE if other.

Method QUEUE:FREE()

 Free() --> TRUE

Free() is removes all items from queue and returns TRUE.

Method QUEUE:GET()

 Get() --> <vData>

Get() is returns first queues element and removes it from queue.

If queue is empty Get() returns NIL.

Method QUEUE:HEAD()

 Head() --> <vData>

Head() is returns first queues element but not removes it from queue.

If queue is empty Head() returns NIL.

Method QUEUE:LEN()

 Len() --> <nLen>

Len() is returns queue length - the count elements into queue.

If queue is empty Len() returns 0.

Method QUEUE:PUT()

 Put(<vData>) --> <nItem>

Put() is inserts new element into queue immediately after to the last element and returns it number.

Method QUEUE:QUEUENEW()

 QueueNew() --> QUEUE object

QueueNew() is constructs and returns new QUEUE object. That class can be use to manipulating( put, get, read) queues made from arbitrary types data.

Method QUEUE:TAIL()

 Tail() --> <vData>

Tail() is returns last queues element but not removes it from queue.

If queue is empty Tail() returns NIL.