anchor.diff:  ;(defgeneric (setf window-viewport-position) (x y clim-stream-pane))
   
   
  -;; CLIM-STREAM-PANE
  +;;; CLIM-STREAM-PANE
   
   (defclass clim-stream-pane (output-recording-stream sheet-leaf-mixin basic-pane)
     ((display-time :initform nil
  
positive.code:     :max-height max-height
      :min-height min-height))
  
  (defclass pane (standard-sheet-input-mixin temporary-medium-sheet-output-mixin
  		sheet-transformation-mixin sheet)
    (
     #+ignore(foreground :initarg :foreground
  	       :initform +black+
  	       :reader pane-foreground)
     #+ignore(background :initarg :background
  	       :initform +white+
  	       :reader pane-background)
     (text-style :initarg :text-style
  	       :initform nil
  	       :reader pane-text-style)
     (name :initarg :name
  	 :initform "(Unnamed Pane)"
  	 :reader pane-name)
     (manager :initarg :manager)
     (port :initarg :port)
     (frame :initarg :frame
  	  :initform *application-frame*
  	  :reader pane-frame)
     (enabledp :initform nil
  	     :initarg :enabledp
  	     :accessor pane-enabledp)
     (sr-width :initform nil :initarg :width)
     (sr-max-width :initform nil :initarg :max-width)
     (sr-min-width :initform nil :initarg :min-width)
     (sr-height :initform nil :initarg :height)
     (sr-max-height :initform nil :initarg :max-height)
     (sr-min-height :initform nil :initarg :min-height)
     (space-requirement :initform (make-space-requirement :width 600 :max-width 600
  							:height 600 :max-height 600)
  		      :accessor pane-space-requirement)
     )
    )
  
  (defmethod medium-foreground ((pane pane))
    (medium-foreground (sheet-medium pane)))
  
negative.code: 
  		    
  
  ;;; INTERACTOR PANES 
  
  (defclass interactor-pane (clim-stream-pane)
    ())
  