anchor.diff:  	   (type fixnum start1 end1 start2 end2))
     (unless (scsu-state-timestamp-vector state)
       (initialize-timestamp state initial-priority string start1 end1))
  -  (with-buffer-accessor (:reader pick-char :current src-current)
  +  (with-buffer-accessor (src-current :reader pick-char)
         (string start1 end1 :element-type character)
  -    (with-buffer-accessor (:writer put-byte :current dst-current)
  +    (with-buffer-accessor (dst-current :writer put-byte)
   	(bytes start2 end2 :element-type (unsigned-byte 8))
         (loop while (< src-current end1)
   	 do (with-scsu-error-handling
  
positive.code:   	   (type fixnum start1 end1 start2 end2)
    	   (type string string))
    (scsu-trace-output "~2&")
    (with-buffer-accessor (:reader pick-byte :current src-current)
        (bytes start1 end1 :element-type (unsigned-byte 8))
      (with-buffer-accessor (:writer put-char :current dst-current)
  	(string start2 end2 :element-type character)
        (loop while (< src-current end1)
  	 do (with-scsu-error-handling
  
negative.code: 		 (slot-value ,%state 'current-timestamp) ,%c-t)
  	   (funcall ,return ,%dst ,%src))))))
  
  (defmacro with-buffer-accessor ((current
  				 &key (reader (gensym) reader-supplied-p)
  				 (writer (gensym) writer-supplied-p))
  				   (buffer start end &key (element-type '*))
  				&body body)
    (alexandria:once-only (buffer start end)
  