public FooClass(IMutableService <ILogger> logger)
 {
     _logger     = logger.CurrentValue;
     _disposable = logger.OnChange(newLogger => _logger = newLogger);
 }
 public InjectedClass(IMutableService <MyService> mutableService)
 {
     _service    = mutableService.CurrentValue;
     _disposable = mutableService.OnChange(service => _service = service);
 }