anchor.diff:  // Program.fs
   open System
  +open System.Collections.Generic
   
   let rec fix f x = f (fix f) x
   
  
positive.code:       | ParserResult.Failure (msg, _, _) -> result.Failure msg
  
  
  [<EntryPoint>]
  let main _ =
     printfn "%A" <| Parser.FromString "hoge"
     printfn "%A" <| Parser.FromString "10"
     printfn "%A" <| Parser.FromString "false"
     printfn "%A" <| Parser.FromString "(a b c + - * / _ !)"
     printfn "%A" <| Parser.FromString "(abc/def a10 (2 3 hoge))"
     printfn "%A" <| Parser.FromString "( 10 fa1   \n 10  )"
  
     printfn "%A" <| Parser.FromString "(10a)"
     printfn "%A" <| Parser.FromString "a b c"
     0
  
negative.code:                 | Number of int
                  | Symbol of string
                  | List of expression list
  
  
  module Parser =
    open FParsec
  