anchor.diff:    (:documentation "The specializer to use for this type in a presentation
   method lambda list"))
   
  -;;; Metaclass for presentation types.  For presentation types not associated 
  +;;; Metaclass for presentation types.  For presentation types not associated
   ;;; with CLOS classes, objects with this metaclass are used as a proxy for the
  -;;; type during presentation method dispatch.  
  +;;; type during presentation method dispatch.
   
   (eval-when (:compile-toplevel :load-toplevel :execute)
     (defclass presentation-type ()
  
positive.code: 	(result-size nil))
      (map-applicable-translators
       #'(lambda (translator presentation context)
  	 (if (and result-context (not (eq result-context context)))
  	     ;; Return inner presentation
  	     (return-from find-innermost-presentation-match
  	       (values result result-translator result-context))
  
negative.code:     (input-context window x y
       &key (frame *application-frame*) modifier-state event)
    (values (find-innermost-presentation-match input-context
                                               (stream-output-history window)
                                               frame
                                               window
                                               x y
                                               event
                                               modifier-state)))
  
  (defun throw-highlighted-presentation (presentation input-context event)
    (let ((x (pointer-event-x event))
  