anchor.diff:    (iterate-elements
      (data data-set)
      (lambda (datum)
  -     (format out "~{~A ~}~C" datum #\Linefeed)))
  +     (format out "~{~S ~}~C" datum #\Linefeed))) ; gnuplot wants strings/labels/... quoted
     (format out "e~C" #\Linefeed))
   
   (defmethod make-plot ((plot-kind symbol) data 
  
positive.code:            (if first?
               (format out "plot")
               (format out ","))
             (format out " '-' with ~A " (style data-set))
             (write-plot-settings data-set out)
             (setf first? nil)
             (incf index))))
  
negative.code:          #+Ignore
           (make-container 'sorted-list-container
                           :key 'first :stable? t) r)))
  
  ;; quick hack - should specialize on 2-D bar charts and extend to other classes
  (defmethod labelsp (plot)
    ;; taking two sec. to figure out CL-CONTAINERS would probably ease this pain...
    (let ((sample-data-point
  	(first-element
  	 (contents (data (first-element (data-sets plot)))))))
      (if (> (length sample-data-point) 3)
  	t)))
  
  (defmethod write-plot ((plot gnuplot) (style (eql :gnuplot)))
    (let ((pathname (fullpath plot))
  