anchor.diff:     */
     static Stream<Map> get onRecord => _streamController.stream;
   
  +  static Function getMetaData;
  +
     /**
      * All [Logger]s in the system.
      */
  
positive.code: class Logger {
  
    final source;
    Function getMetaData;
    Level logLevel = null;
    Logger _parent;
    static StreamController _streamController =
  
negative.code:    * actual instance whenever it is called with the same string name.
     * Creates root logger with logLevel set if not created.
     */
    factory Logger(String source) {
      return _loggers.putIfAbsent(source, source == "" ? _createRootLogger : () => new Logger._named(source));
    }
  
  