tryUpdate method
Update value with error handling
Implementation
RxResult<V> tryUpdate(K key, V Function(V value) update,
{V Function()? ifAbsent}) {
return RxResult.tryExecute(() {
final newMap = Map<K, V>.from(value);
final result = newMap.update(key, update, ifAbsent: ifAbsent);
value = newMap;
return result;
}, 'update map value');
}