Dart optionals

Optionals.dart

String? nullString = 'Abdulloh';

void main() {
  nullString = null;
  
  print (isNullString(nullString));
}

bool isNullString(String? someNullablesString) {
  if (someNullablesString == null) {
    return true;
  }
  
  return false;
}