anchor.diff:  
     /// Profile component view construction performance.
     build,
  -
  -  /// Profile component bindings (accessed methods and getters in components).
  -  binding,
   }
   
   Profile _toProfile(dynamic profile, void log(dynamic message)) {
  
positive.code:       return Profile.none;
      case 'build':
        return Profile.build;
      case 'binding':
        return Profile.binding;
      default:
        log('Invalid flag for "$_argProfileFor": $profile.');
        return Profile.none;
  
negative.code:     )
      ..addOption(
        _argProfileFor,
        valueHelp: '"build"',
        defaultsTo: null,
        help: ''
            'Whether to emit additional code that may be used by tooling '
  