anchor.diff:               (format s "~{~&  ~A [ shape=doublecircle ];~}" final)
                (map 'nil (lambda (x)
                            (format s "~&  ~A -> ~A [label=\"~A\"];~%"
  -                                 (first x) (third x) (second x)))
  +                                 (first x) (third x) (token-label (second x))))
                     d)
                (format s "~&}~%"))
              (dot (ext)
  
positive.code:        (with-output-to-string (s)
           (helper s))))))
  
  
negative.code: final: list of accept states
  start: start state
  output: output file, type determined by suffix (png,pdf,eps)"
    (labels ((token-label (name)
               (if (eq :epsilon name)
                   "&epsilon;" ; print epsilons in greek
                   name))
             (helper (s)
               (format s "~&digraph {~%")
               (when start
                 (format s "~&  start[shape=none];")
  