anchor.diff:        (make-translation-transformation (+ dx1 dx2) (+ dy1 dy2)))))
   
   (defmethod compose-transformations
  -    (transformation2 (transformation1 standard-identity-transformation))
  +    ((transformation2 transformation) (transformation1 standard-identity-transformation))
     transformation2)
   
   (defmethod compose-transformations
  -    ((transformation2 standard-identity-transformation) transformation1)
  +    ((transformation2 standard-identity-transformation) (transformation1 transformation))
     transformation1)
   
   (defmethod invert-transformation
  
positive.code:   t)
  
  (defmethod transformation-equal ((t1 standard-identity-transformation)
                                   (t2 t))
    nil)
  
  (defmethod transformation-equal ((t2 t)
                                   (t1 standard-identity-transformation))
    nil)
  
  
negative.code:            (coordinate= dy1 dy2)))))
  
  (defmethod transformation-equal ((t1 standard-translation)
                                   (t2 transformation))
    nil)
  
  (defmethod transformation-equal ((t2 transformation)
                                   (t1 standard-translation))
    nil)
  