anchor.diff:  }
   
   final ChatAPI = {
  -  'subscribeToFriendStatus': (int id, Function handleStatusChange) => handleStatusChange({'isOnline': id % 2 == 0 ? true : false}),
  +  'subscribeToFriendStatus': (int id, Function handleStatusChange) =>
  +      handleStatusChange({'isOnline': id % 2 == 0 ? true : false}),
     'unsubscribeFromFriendStatus': (int id, Function handleStatusChange) => handleStatusChange({'isOnline': false}),
   };
   
  
positive.code: _friendListItem(Map props) {
    final isOnline = useFriendStatus(props['friend']['id']);
  
    return react.li({'style': {'color': isOnline.value ? 'green' : 'black'}}, [props['friend']['name']]);
  }
  
  void main() {
  
negative.code:   void handleStatusChange(Map status) {
      isOnline.set(status['isOnline']);
    }
  
    useEffect(() {
      ChatAPI['subscribeToFriendStatus'](friendID, handleStatusChange);
      return () {
  