anchor.diff:      
       let run () =
           match !testFile, !feName , !generatorName with
  -        | None, None, None                               -> ()
           | Some(fName), Some(feName), Some(generatorName) -> 
               let grammarFilePath = System.IO.Path.Combine((!testsPath).Value, fName)
               let fe =
  
positive.code:         "Generator with name " + genName + " is not available. Run \"Main.exe -ag\" for get all available generators.\n"
          |> System.Console.WriteLine
      | EmptyArg (argName)       ->
          "Argument can not be empty: " + argName + "\n"
          |> System.Console.WriteLine
      | FEError (error)          ->
          "Frontend error: " + error + "\n"
          |> System.Console.WriteLine
  
negative.code:             printf "%A" result
  #endif
              ()
          | _, None, _          -> EmptyArg "frontend name (-f)" |> raise
          | _, _, None          -> EmptyArg "generator name (-g)" |> raise
          | None , _, _         -> EmptyArg "file name (-t)" |> raise 
      try
          if !generateSomething = true then 
              run ()
      with 
      | InvalidFEName (feName)   -> 
          "Frontend with name " + feName + " is not available. Run \"Main.exe -af\" for get all available frontends.\n" 
  