anchor.diff:  
     /// Creates a new XmlNodeTypeException.
     XmlNodeTypeException(String message) : super(message);
  +
  +  @override
  +  String toString() => 'XmlNodeTypeException: $message';
   }
   
   /// Exception thrown when the parent relationship between nodes is invalid.
  
positive.code:   /// Creates a new XmlTagException for a missing closing tag.
    factory XmlTagException.missingClosingTag(String name) =>
        XmlTagException('Missing closing tag </$name>.');
  }
  
negative.code:   int? get offset => position;
  
    @override
    String toString() => 'XmlParserException: $message at $line:$column';
  }
  
  /// Exception thrown when an unsupported node type is used.
  