anchor.diff:  			(cond ((eq ,char-var #\newline)
   			       ;; we proceed to line+1 : -1, so that the next character read 
   			       ;;  (which will be the leftmost on the line) will be at line+1 : 0
  +			       ;; current-byte was incremented above, so we don't need to touch that here
   			       (incf current-line)
   			       (setq current-column -1)
   			       ,newline-action)
  
positive.code:     (let ((tokens nil))
        (with-open-file (stream file) 
  	(let ((ps-stream (make-pseudo-stream :unread-chars nil :stream stream))
  	      ;; The upper-left corner of the file is considered 1:0 (line 1, column 0)
  	      ;; so the character one to the left of that is 1:-1 (line 1, column -1).
  	      ;; So we are at 1:-1 before we read the first character.
  	      (pre-byte 0) (pre-line 1) (pre-column -1))
  	  (loop do
  	    (multiple-value-bind (type value 
  				       first-byte first-line first-column
  
negative.code: 				(cond ((eq temp-char #\newline)
  				       ;; we proceed to line+1 : -1, so that the next character read 
  				       ;;  (which will be the leftmost on the line) will be at line+1 : 0
  				       ;; current-byte was incremented above, so we don't need to touch that here
  				       (incf current-line)
  				       (setq current-column -1))
  				      (t
  