|An anonymous user wrote|
on October 4th, 2007 at 07:17 pm
change-classcan be put to good use. You've got an abstract class (a
clipping-path) and three concrete representation classes. You are using
change-classto transparently switch representations as needed.
(let ((my-fish (get-fish *aquarium*)))
(change-class my-fish 'bicycle)
(shift-gears my-fish 3))