anchor.diff:              then
                   visited.[topV] <- true
                   for v in graphFst.OutEdges(topV) do
  -                    if (isAct v.Target)
  -                    then 
  -                        new TokenEdge<_>(v.Target, v.Source, match v.Tag.InSymb with |Smbl y -> y | _ -> failwith "Unexpected!!!" ) |> edgesToks.Add |> ignore
  -                        if (isEps v.Target) then queueV.Enqueue(v.Target)
  -                    else 
  -                        new TokenEdge<_>(v.Target, v.Source, match v.Tag.InSymb with |Smbl y -> y | _ -> failwith "Unexpected!!!" ) |> edgesToks.Add |> ignore
  -                        queueV.Enqueue(v.Target)  
  +                    new TokenEdge<_>(v.Target, v.Source, match v.Tag.InSymb with |Smbl y -> y | _ -> failwith "Unexpected!!!" ) |> edgesToks.Add |> ignore
  +                    if isAct v.Target
  +                    then if (isEps v.Target) then queueV.Enqueue(v.Target)
  +                    else queueV.Enqueue(v.Target)  
                                              
           let gr = new GraphTokenValue<_>() 
           gr.AddVerticesAndEdgeRange edgesToks |> ignore
  
positive.code: 
      let idFunction v = 
          for edge in inputFstLexer.OutEdges(v) do
              if not <| (edge.Tag.OutSymb = Eps)
              then 
                  idF := match edge.Tag.OutSymb with |Smbl y -> y | _ -> failwith "Unexpected :(" 
          !idF    
  
negative.code: open QuickGraph
  open YC.FST.FstApproximation
  
  let printSmbString (x:char*Position<_>) = 
          (fst x).ToString() + "_br: " + (snd x).back_ref + "(" + (snd x).start_offset.ToString() + "," + (snd x).end_offset.ToString() + ")"
  
  type TokenEdge<'br when 'br:comparison>(s,e,t)=
      inherit TaggedEdge<int, char*Position<'br>>(s,e,t)
  