Class Redefinition

[David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>]

    Date: 24 Jul 87  1645 PDT
    From: Dick Gabriel <RPG@SAIL.STANFORD.EDU>
    ....
    Something like this should work:

    (let
     ((obsolete-class (class-named 'heh-heh))
      (new-class (make-instance 'standard-class ...))) ;make an anonymous class
						       ;that is the new HEH-HEH
     (add-method 
      #'class-changed
      (make-method	;later, make-instance
       ()
       `(,obsolete-class ,new-class)
       #'...))
     (name-that-class new-class 'heh-heh))             ;Hm, what is this function?

This doesn't conform to 87-002's specification that redefining a class
updates the existing class object, rather than replacing it with a new
class object.  Indeed, if we changed that, we wouldn't need the concept
of "obsolete classes", as I pointed out in my message of early Saturday
morning (sent after you wrote this message, but before I saw your message;
we've had a lot of network problems lately, first with window-caulkers
parking their scaffolding in the middle of the through-the-air segment
of our network for a week, then MIT air conditioning failure, and who
knows what else.)  However, because methods are classified by class
objects rather than class names, replacing the old class object with a
new one has its own complexities.