anchor.diff:     )
     )
   
  - 
   ;;; Basic-Pane class
   
  
positive.code: 	   (allocate-space child new-width new-height)
  	   (incf y new-height))))
  
  
negative.code:    (enabledp :initform nil
  	     :initarg :enabledp
  	     :accessor pane-enabledp)
     (space-requirement :initarg :space-requirement
  		      :initform (make-space-requirement :width 100 :max-width 100
  							:height 100 :max-height 100)
  		      :accessor pane-space-requirement)
     )
  