anchor.diff:  
           use out = new System.IO.StreamWriter (path : string)
           out.WriteLine("digraph AST {")
  -        let createNode num isAmbiguous nodeType (str : string) =
  +        let createNode num isAmbiguous isTerminal nodeType (str : string) =
               let label =
                   let cur = str.Replace("\n", "\\n").Replace ("\r", "")
                   if not isAmbiguous then cur
  
positive.code:                 | AstNode -> ",shape=box"
                  | Prod -> ""
              let color =
                  if not isAmbiguous then ""
                  else ",style=\"filled\",fillcolor=red"
              out.WriteLine ("    " + num.ToString() + " [label=\"" + label + "\"" + color + shape + "]")
          let createEdge (b : int) (e : int) isBold (str : string) =
  
negative.code:                     then indToString leftSide.[children.first.prod]
                      else "error"
                       
                  createNode i (children.other <> null) false AstNode ("n " + label)
                       
                  let inline handle (family : OtherFamily) =
                      let u = next()
                      createNode u false false Prod ("prod " + family.prod.ToString())
                      createEdge i u true ""
                      family.nodes.doForAll <| fun child ->
                          let v = 
  