anchor.diff:              needing to convert/validate it manually. *)
   
   ////
  -//type ArgInfo<'T> = {
  +//type TypedArgInfo<'T> = {
   //    //
   //    ShortName : char option;
   //    //
  +//    ShortAliases : Set<char>;
  +//    //
   //    Name : string;
  +//    //
  +//    Aliases : Set<string>;
   //    //
   //    Description : string option;
   //    //
   //    DefaultValue : 'T option;
   //}
  +//
  +//module Example =
  +//    /// Help options.
  +//    let helpArgInfo : TypedArgInfo<unit> = {
  +//        ShortName = Some 'h';
  +//        ShortAliases = Set.singleton '?';
  +//        Name = "help";
  +//        Aliases = Set.empty;
  +//        Description = Some "Display this list of options.";
  +//        DefaultValue = None;
  +//    }
  +
   
   (*  The code below is from the F# PowerPack and is only temporary --
       eventually it will be replaced with a new, functional-style API. *)
  
positive.code: 
      /// Prints the help for each argument.
      static member Usage (specs, ?usage) =
          let usage = defaultArg usage ""
          System.Console.Error.WriteLine (getUsage (Seq.toList specs) usage)
  
      #if FX_NO_COMMAND_LINE_ARGS
      #else
  
negative.code:                                 raise <| Bad (getUsage argSpecs usageText)
                           f arg2
                           cursor := !cursor + 2
                      | Float f ->
                           let arg2 =
                              let arg2 = getSecondArg ()
                              try float arg2
  