anchor.diff:      let tokenize actions (lexbuf:LexBuffer<_,_>) printG =
           //let edgesSeq = edgesSeq |> Array.ofSeq
           let add (edg:LexerEdge<_,_>) (newStt:State<_,_>) =
  -            match lexbuf.States.[edg.Target]
  -                  |> ResizeArray.tryFind(fun (x:State<_,_>) -> x.AcceptAction = newStt.AcceptAction && x.StateID = newStt.StateID)
  -                with
  +            let x = 
  +                lexbuf.States.[edg.Target]
  +                |> ResizeArray.tryFind 
  +                    (fun (x:State<_,_>) -> x.AcceptAction = newStt.AcceptAction && x.StateID = newStt.StateID)
  +            match x with
               | Some x ->
                   newStt.Info
                   |> ResizeArray.iter(
                       fun i -> 
                           if x.Info.Exists(fun j -> j.StartV = i.StartV
  -                                                  && i.AccumulatedString.Count = j.AccumulatedString.Count
  -                                                  && ResizeArray.forall2 (=) i.AccumulatedString j.AccumulatedString) 
  +                                                  && i.AccumulatedString.Length = j.AccumulatedString.Length
  +                                                  && List.forall2 (=) i.AccumulatedString j.AccumulatedString) 
                              |> not
                           then x.Info.Add i)
               | None -> lexbuf.States.[edg.Target].Add newStt
  
positive.code:         let r = newEdgs
          res.AddVerticesAndEdgeRange r
          |> ignore
          //EpsClosure.NfaToDfa res
          //|> ignore
          let eps_res = EpsClosure.NfaToDfa res
          eps_res
                            
  
negative.code:                                 if i.Positions.Count = 0 then None else Some i.Positions.[0] 
                                  |> newPos
                              new StateInfo<_,'br>((match stt.PreviousV with | Some x -> x | None -> i.StartV)
                              , ch::i.AccumulatedString
                              , ResizeArray.concat [ResizeArray.singleton pos; i.Positions])
                      )
              else 
                  new StateInfo<_,'br>((match stt.PreviousV with | Some x -> x | None -> edg.Source)
                  , ch::[]
                  , ResizeArray.singleton (newPos (Some lexbuf.CurrentPos)))
                  |> ResizeArray.singleton
  
  