anchor.diff:          then "Empty Node"
           else 
               if this.parents.IsEmpty
  -            then "Start Node"
  +            then "Entry Node"
               elif this.children.IsEmpty
  -            then "Finish Node"
  +            then "Exit Node"
               else "Node"
   
   type BlockEdge<'TokenType>(source, target, tag) = 
  
positive.code:                 interNode.children
                  |> List.iter (fun block -> printBlock block nodeNumber)
                      
          printInterNode this.Start -1
  
          out.WriteLine("}")
          out.Close()
negative.code:                                 processBlock child
                      )
  
          processInterNode entry []
  
          !errorList
  
      member this.Entry = entry
      member this.Exit = exit
  
      member this.FindUndefVariable() = findUndefVariable()
  
      member this.PrintToDot name = 
          let count = ref -1
          let blockToNumber = new Dictionary<_, _>()
          let interNodeToNumber = new Dictionary<_, _>()
          
          use out = new StreamWriter (name : string)
          out.WriteLine("digraph AST {")
  
          let rec printBlock (block : Block<'TokenType>) parentNumber = 
  