anchor.diff:    (make-extremums-children-ratio rack (sheet-children rack) :width nil))
     
   (defmethod allocate-space ((rack vrack-pane) width height)
  -  (set-width-and-height rack width height)
  +  (resize-sheet rack width height)
     (allocate-space-internal rack height nil)
     (loop for child in (sheet-children rack)
   	for nh = (slot-value child 'new-height)
   	and y = 0 then (+ y nh)
  -	do (multiple-value-bind (x1 y1)
  -	       (bounding-rectangle* (sheet-region child))
  -	     (setf (sheet-transformation child)
  -		   (make-translation-transformation (- x1) (- y y1))))
  +        do (move-sheet child 0 y)
   	   (allocate-space child width nh)))
   
   ;;; TABLE PANE
  
positive.code: 
  (defmethod scroll-extent ((pane basic-pane) x y)
    (when (is-in-scroller-pane pane)
      (let ((transform (sheet-transformation pane)))
        (multiple-value-bind (old-x old-y)
            (transform-position transform 0 0)
          (setf (sheet-transformation pane)
                (compose-translation-with-transformation
                 transform (- x old-x) (- y old-y)))))
      (update-scroll-bars pane (sheet-region pane) x y)
      (dispatch-repaint pane (sheet-region pane))))
  
  
negative.code: ;;;           Robert Strandh (strandh@labri.u-bordeaux.fr)
  ;;;  (c) copyright 2001 by
  ;;;           Lionel Salabartan (salabart@emi.u-bordeaux.fr)
  ;;;           Arnaud Rouanet (rouanet@emi.u-bordeaux.fr)
  
  ;;; This library is free software; you can redistribute it and/or
  ;;; modify it under the terms of the GNU Library General Public
  