Introduction to OOP Chapter 21: Software Frameworks : next previous audio real text

Simulation Framework from Chapter 7

Here is a framework like we might use in Chapter 7 (the billiards game). 
GraphicalObject = object
		(* data fields *)
	link : GraphicalObject;
	region : Rect;

		(* initialization function *)
	procedure setRegion (left, top,  right, bottom : integer);

		(* operations that graphical objects perform *)
	procedure draw;
	procedure update;
	function intersect (anObj : GraphicalObject) :  boolean;
	procedure hitBy (anObj : GraphicalObject);
end;
Intro OOP, Chapter 21, Slide 15