anchor.diff:              |> List.distinct
   
           let fileExt =
  -            argValue "--extension" args |> Option.defaultValue (defaultFileExt typescript args)
  +            argValueMulti ["-e"; "--extension"] args
  +            |> Option.defaultValue (defaultFileExt typescript args)
   
           let compilerOptions =
               CompilerOptionsHelper.Make(typescript = typescript,
  
positive.code: Arguments:
    --cwd             Working directory
    -o|--outDir       Redirect compilation output to a directory
    --extension       Extension for generated JS files (default .fs.js)
    -s|--sourceMaps   Enable source maps
  
    --define          Defines a symbol for use in conditional compilation
  
negative.code: let clean args dir =
      let typescript = flagEnabled "--typescript" args
      let ignoreDirs = set ["bin"; "obj"; "node_modules"]
  
      let fileExt =
          argValueMulti ["-e"; "--extension"] args
          |> Option.defaultValue (defaultFileExt typescript args)
  
      let dir =
          argValueMulti ["-o"; "--outDir"] args
          |> Option.defaultValue dir
          |> IO.Path.GetFullPath
  
      // clean is a potentially destructive operation, we need a permission before proceeding
      Console.WriteLine("This will recursively delete all *{0}[.map] files in {1}", fileExt, dir)
  