anchor.diff:          ? callArgs('getLineTokens', [line, precise])
           : callArg('getLineTokens', line);
       if (result is List) {
  -      return result.map((t) => new Token.fromProxy(t)).toList();
  +      return result.map((t) => new Token.fromProxy(t)).toList() as List<Token>;
       } else {
         return [];
       }
  
positive.code:   String get mode => jsProxy['mode'];
  
    /// The mode's file extension.
    List<String> get ext => jsProxy['ext'];
  
    /// The mode's other file extensions.
    List<String> get alias =>
  
negative.code:   List<TextMarker> findMarksAt(Position pos) {
      var result = callArg('findMarksAt', pos.toProxy());
      if (result is! List) return [];
      return result.map((mark) => new TextMarker(mark)).toList() as List<TextMarker>;
    }
  
    /**
  