anchor.diff:     (default
          interactor)))
   
  -(define-graph-test-command foo ()
  +(define-graph-test-command (com-foo :name t) ()
     (with-text-style (*query-io* (make-text-style :sans-serif nil 12))
       (let ((*print-case* :downcase))
         (format-graph-from-roots
  
positive.code: 			      (layout-edges graph node stream arc-drawer arc-drawing-options))
                              (map nil continuation children))))))
  
  (defmethod layout-graph-edges :around ((graph-output-record tree-graph-output-record)
                                         stream arc-drawer arc-drawing-options)
    (setf arc-drawer (or arc-drawer #'standard-arc-drawer))
    (call-next-method graph-output-record stream arc-drawer arc-drawing-options))
  
  (defmethod layout-graph-edges :around ((graph-output-record digraph-graph-output-record)
                                         stream arc-drawer arc-drawing-options)
    (setf arc-drawer (or arc-drawer #'arrow-arc-drawer))
    (call-next-method graph-output-record stream arc-drawer arc-drawing-options))
  
  (defmethod layout-graph-edges :around ((graph-output-record dag-graph-output-record)
                                         stream arc-drawer arc-drawing-options)
    (setf arc-drawer (or arc-drawer #'standard-arc-drawer))
    (call-next-method graph-output-record stream arc-drawer arc-drawing-options))
  
  (defun standard-arc-drawer (stream from-node to-node x1 y1 x2 y2
  
negative.code:   (apply #'draw-line* stream x1 y1 x2 y2 drawing-options))
  
  (defun arrow-arc-drawer (stream from-node to-node x1 y1 x2 y2
                           &rest drawing-options
                           &key &allow-other-keys)
    (if (eq from-node to-node)
        (let ((rad 8))
          (apply #'draw-circle*
                 stream (- x1 rad -2) (- y1 rad) rad
                 :filled nil :end-angle (* pi 1.5) drawing-options)
          (apply #'draw-arrow*
                 stream (- x1 rad -2) y1 x1 y1 drawing-options))
        (apply #'draw-arrow* stream x1 y1 x2 y2 drawing-options)))
  
  #||
  
  