anchor.diff:  }
   
   void parseCommandLine(List<OptionHandler> handlers, List<String> argv) {
  +  // TODO(ahe): Use ../../args/args.dart for parsing options instead.
     var patterns = <String>[];
     for (OptionHandler handler in handlers) {
       patterns.add(handler.pattern);
  
positive.code:   List<OptionHandler> handlers = <OptionHandler>[
      new OptionHandler('--throw-on-error', (_) => throwOnError = true),
      new OptionHandler('--suppress-warnings', (_) => showWarnings = false),
      new OptionHandler('--verbose', (_) => verbose = true),
      new OptionHandler('--library-root=.*', (String argument) {
        String path = nativeToUriPath(extractParameter(argument));
        if (!path.endsWith("/")) path = "$path/";
        libraryRoot = cwd.resolve(path);
      }),
      new OptionHandler('--out=.*', (String argument) {
        explicitOut = true;
        out = cwd.resolve(nativeToUriPath(extractParameter(argument)));
      }),
      new OptionHandler('--allow-mock-compilation', passThrough),
      new OptionHandler('--no-colors', (_) => colors.enabled = false),
      new OptionHandler('--enable-checked-mode|--checked|-c',
                        (_) => passThrough('--enable-checked-mode')),
      new OptionHandler('--help', (_) => helpAndExit()),
      // The following two options must come last.
      new OptionHandler('-.*', (String argument) {
        helpAndFail('Error: Unknown option "$argument".');
  
negative.code: 
    parseCommandLine(handlers, argv);
  
    if (wantHelp) helpAndExit(verbose);
  
    if (arguments.isEmpty()) {
      helpAndFail('Error: No Dart file specified.');
    }
  