anchor.diff:  (defclass floating-window (window) ())
   
   (defun make-floating-window (buffer x y width height use-modeline-p)
  -  (let ((window (%make-window 'floating-window buffer x y width height use-modeline-p)))
  +  (let ((window (make-instance 'floating-window
  +                               :buffer buffer
  +                               :x x
  +                               :y y
  +                               :width width
  +                               :height height
  +                               :use-modeline-p use-modeline-p)))
       (push window *floating-windows*)
       window))
   
   (defmethod %delete-window ((window floating-window))
     (setf *floating-windows*
  -        (delete window *floating-windows*))
  -  t)
  +        (delete window *floating-windows*)))
   
   (defun balloon (orig-window buffer width height)
     (let* ((y (+ (window-y orig-window)
  
positive.code:     :initform nil
      :accessor window-parameters)))
  
  (defgeneric %delete-window (window))
  
  (defun windowp (x)
    (typep x 'window))
  
  (defun %make-window (class-name buffer x y width height use-modeline-p)
    (make-instance class-name
                   :x x
                   :y y
                   :width width
                   :height height
                   :%buffer buffer
                   :screen (make-screen x y width height use-modeline-p)
                   :view-point (copy-point (buffer-point buffer) :right-inserting)
                   :use-modeline-p use-modeline-p
                   :point (copy-point (buffer-start-point buffer) :right-inserting)))
  
  (defun make-window (buffer x y width height use-modeline-p)
    (%make-window 'window buffer x y width height use-modeline-p))
  
  (defun window-x (&optional (window (current-window)))
    (window-%x window))
  
negative.code:     :initarg :height
      :accessor window-%height
      :type fixnum)
     (buffer
      :initarg :buffer
      :accessor window-%buffer
      :type buffer)
     (screen
      :reader window-screen)
     (view-point
      :reader window-view-point
      :writer set-window-view-point
      :type point)
     (point
      :accessor %window-point
      :type point)
     (delete-hook
  