anchor.diff:  
   ;; --
   
  -;; FIXME: Test DEFSINGLETON with forward-referenced direct superclasses
  -
  -;; FIXME: Test DEFSINGLETON with a SINGLETON superclass of a direct superclass
  +;; FIXME: Test DEFSINGLETON with a SINGLETON superclass of a direct
  +;; superclass not repreenting a SINGLETON
   
   (eval-when ()
   
  
positive.code: ;; )
  
  (eval-when ()
    ;; FIXME: Not very rigorous tests onto the updated SHARED-INITIALIZE
  
    (defsingleton x-a () ;; FIXME SINGLETON no longer appearing in the X-A CPL
      ())
  
    (typep (make-instance 'x-a) 'x-a)
  
negative.code: 
            `(progn
  
               ;; NB: This implementation, in effect, prevents any usage
               ;; of forward-referenced classes in the SUPERCLASSES list
  
               (defclass ,%proto-name (,@user-metaclass prototype-class
                                                        ,@superclasses)
  