Best way to access state variables

[dlewis2017]

Hello,

What's the best way to access state variables as you would normally do without freezed? There seems to be multiple ways such as
maybeWhen, maybeOrNull, when, etc.
More specifically, what's the best way to access optional state parameters that can be null? For example I want .whenOrNull to return one, optional, variable when a state gets emitted. The result from loaded in below example of state.whenOrNull seems to throw an error when position isn't defined expecting it to be.

E.g.

if (state is SuccessState) {
   LoadSomething(state.position);
}

Position? position = state.whenOrNull(
   loaded: (Position? position, String? manualLocation, List<String> valuesArray) => position