Common Lisp the Language, 2nd Edition
 
 
 
  
  
  
  
 
 Next:  Changing the Class 
Up:  Redefining Classes
 Previous:  Customizing Class Redefinition
 

There are two allowed extensions to class redefinition:
-   The Object System may be extended to permit the new class
to be an instance of a metaclass other than the metaclass of the
old class.
 
-   The Object System may be extended to support an updating process
when either the old or the new class is an instance of a
class other than standard-class that is not a built-in class.
 
 
AI.Repository@cs.cmu.edu