anchor.diff:  	  and y = 0 then (+ y nh)
   	  and nw = (/ (* width (get-pane-width child)) (get-pane-width box))
   	  do (move-sheet child 0 y)
  -	     (setf nw (do-in nw (sr-min-width child) (sr-max-width child)))
  +	     (setf nw (clamp nw (sr-min-width child) (sr-max-width child)))
   	     (allocate-space child (round nw) nh)))
     
   ;;; HRACK-PANE
  
positive.code: (defun make-pane (type &rest args)
    (apply #'make-pane-1 *pane-realizer* *application-frame* type args))
  
  ;; dummy but useful
  (defmacro do-in (size min max)
    `(max ,min (min ,max ,size)))
  
  (defun get-pane-width (pane)
    ;; Give the region size if already set, otherwise, give the space-requirement
  
negative.code:     :max-height max-height
      :min-height min-height))
  
  (defmethod space-requirement-components ((space-req standard-space-requirement))
    (with-slots (width min-width max-width height min-height max-height) space-req
      (values width min-width max-width height min-height max-height)))
  
  