anchor.diff:  (defun move-end-of-line (buffer)
     (let ((point (buffer-point buffer)))
       (setf (mark-charpos point) (line-length (mark-line point))))
  +  (values))
  +
  +(defun move-beginning-of-buffer (buffer)
  +  (setf (mark-line (buffer-point buffer)) (first-line buffer)
  +        (mark-charpos (buffer-point buffer)) 0)
  +  (values))
  +
  +(defun move-end-of-buffer (buffer)
  +  (let ((point (buffer-point buffer)))
  +    (setf (mark-line point) (last-line buffer)
  +          (mark-charpos point) (line-length (mark-line point))))
     (values))
   
   (defun move-mark (mark &optional (n 1))
  
positive.code:                                         :frame frame
                                          :buffer (make-instance 'buffer)))
                 (*last-command* nil)
                 (*last-character* nil))
            (initialize-global-key-map *editor*)
            (mezzanine.gui.widgets:draw-frame frame)
            (multiple-value-bind (left right top bottom)
                (mezzanine.gui.widgets:frame-size (frame *editor*))
  
negative.code:   (move-mark-to-mark mark (buffer-point buffer)))
  
  (defun mark-at-point-p (buffer mark)
    (mark= mark (buffer-point buffer)))
  
  (defun start-of-line-p (mark)
    (eql (mark-charpos mark) 0))
  