anchor.diff:              | Groonga_Path _ -> "specify groonga.exe path."
               | DB_Path _ -> "specify Groonga database path."
               | Encoding _ -> "Specify encoding such as UTF-8."
  -            | Pritty _ -> "Output pritty printed."
  +            | Pretty _ -> "Output pritty printed."
   
   // build the argument parser
   let parser = ArgumentParser.Create<CLIArguments>()
  
positive.code:         inputs |> List.map (fun s -> writer.Write s) |> ignore
          writer.Close()
      let stdout = p.StandardOutput.ReadToEnd()
      if config.Pritty then
          stdout |> pritty_print |> printfn "-> %s"
      else
          stdout |> printfn "-> %s"
      p.Close()
  
negative.code:     let utf8Str = utf8.GetString(utf8Bytes)
      utf8Str
  
  let pretty_print (json: string) =
      let parsedJson = JsonConvert.DeserializeObject(json)
      JsonConvert.SerializeObject(parsedJson, Formatting.Indented)
  
  