anchor.diff:  
   (defmethod trivial-gray-streams:stream-write-char ((stream buffer-output-stream) char)
     (prog1 char
  -    (buffer-insert-char (buffer-output-stream-buffer stream)
  -                        (buffer-output-stream-linum stream)
  -                        (buffer-output-stream-charpos stream)
  -                        char)
  -    (if (char= char #\newline)
  -        (progn
  -          (incf (buffer-output-stream-linum stream))
  -          (setf (buffer-output-stream-charpos stream) 0))
  -        (incf (buffer-output-stream-charpos stream)))))
  +    (marker/insert-char (buffer-output-stream-marker stream)
  +                        char)))
   
   (defun %write-string-to-buffer-stream (stream string start end &key)
  -  (let ((strings
  -         (split-string (subseq string start end)
  -                       #\newline)))
  -    (loop :for s :on strings :do
  -      (buffer-insert-line (buffer-output-stream-buffer stream)
  -                          (buffer-output-stream-linum stream)
  -                          (buffer-output-stream-charpos stream)
  -                          (car s))
  -      (incf (buffer-output-stream-charpos stream) (length (car s)))
  -      (when (cdr s)
  -        (buffer-insert-newline (buffer-output-stream-buffer stream)
  -                               (buffer-output-stream-linum stream)
  -                               (buffer-output-stream-charpos stream))
  -        (incf (buffer-output-stream-linum stream))
  -        (setf (buffer-output-stream-charpos stream) 0)))
  -    string))
  +  (marker/insert-string (buffer-output-stream-marker stream)
  +                        (subseq string start end))
  +  string)
   
   (defun %write-octets-to-buffer-stream (stream octets start end &key)
     (let ((octets (subseq octets start end)))
  
positive.code:                                                point
                                                 interactive-update-p)
    (make-instance class-name
                   :buffer buffer
                   :linum (if point
                              (point-linum point)
                              1)
                   :charpos (if point
                               (point-charpos point)
                               0)
                   :interactive-update-p interactive-update-p))
  
  (defun make-buffer-output-stream (&optional (buffer (current-buffer))
  
negative.code:   (%write-string-to-buffer-stream stream string start end))
  
  (defmethod trivial-gray-streams:stream-terpri ((stream buffer-output-stream))
    (prog1 (marker/insert-char (buffer-output-stream-marker stream)
                               #\newline)
      (buffer-output-stream-refresh stream)))
  
  (defmethod trivial-gray-streams:stream-finish-output ((stream buffer-output-stream))
    (buffer-output-stream-refresh stream))
  