anchor.diff:       (class decorator-class)
        (object decorator-object)
        slot)
  -  (if (equalp (closer-mop:slot-definition-name slot) 'decoratee)
  +  (if (not (decorate-slot-p slot))
         (call-next-method)
         (setf (slot-value (decoratee object)
   			(closer-mop:slot-definition-name slot))
  
positive.code:     ((class decorator-class)
       (object decorator-object)
       slot)
    (if (equalp (closer-mop:slot-definition-name slot) 'decoratee)
        (call-next-method)
        (slot-boundp (decoratee object)
  		   (closer-mop:slot-definition-name slot))))
  
negative.code:     ((class decorator-class)
       (object decorator-object)
       slot)
    (if (not (decorate-slot-p slot))
        (call-next-method)
        (slot-makunbound (decoratee object)
  		       (closer-mop:slot-definition-name slot))))
  
  (defmethod decorate-slot-p (slot)
    t)
  
  (closer-mop:finalize-inheritance (find-class 'decorator-class))
  (closer-mop:finalize-inheritance (find-class 'decorator-object))
  
  ;; Test
  
  