CLSQUEUE.srvscr

/********************************************************************************
Description.. :	FIFO data structure

Methods...... : 	size() - returns the length of the queue.
			put()  - enqueues an item
			peek() - returns the top element, without dequeueing it
			get()  - returns and removes the top element

Returns...... :	- 

Author....... :	ZWOLAKT
Date......... : 2012-06-14
********************************************************************************
_______________________________________________________________________________

Ticket #..... :	
Modification. : 
Author....... :	
Date......... :	
_______________________________________________________________________________
********************************************************************************/;

:CLASS Queue;

:DECLARE _queue;

:PROCEDURE constructor;

	/* initialize the queue array ;
	Me:_queue := {};
	
:ENDPROC;

:PROCEDURE size;
	
	/* return the number of items in the queue ;
	:RETURN Len( Me:_queue );

:ENDPROC;

:PROCEDURE peek;
	/* return the top element without dequeuing it ;
	
	/* copy the item to memory ;
	:RETURN Me:_queue[1];
	
:ENDPROC;

:PROCEDURE put;
	:PARAMETERS item;
	
	/* enqueue item ;
	aAdd( Me:_queue, item );
	
	
:ENDPROC;

:PROCEDURE get;

	:DECLARE item;
	
	:IF Len( Me:_queue ) = 0 ;
		RaiseError( "Queue Size is Zero!", "DataStructures.clsQueue:pop()", 12535 );
	:ENDIF;
	
	/* copy the first item to memory ;
	item := Me:peek();
	
	/* Delete the first item ;
	DelArray( Me:_queue, 1 );
	
	:RETURN item ;
	
:ENDPROC;