Simplify AsyncView - #11

Could you please provide an example of how it disables type inference?

Using AsyncState disables type inference, because by first calling getAsyncState and then acting based on its result, Typescript can no longer infer whether data or error are available. Thus it requires type casting with the keyword as or optional chaining with ?..

If one was to use AsyncState, he could write something like the following:

const asyncState = getAsyncState(data, error);

return (
  <div>
      {asyncState === AsyncState.FINISHED_WITH_ERROR && (
        <RequestError>{error?.response?.data.message}</RequestError>
      )}
  </div>
)

This requires the use of error? instead of simply error, because Typescript cannot understand that if getAsyncState returns FINISHED_WITH_ERROR, error must be defined. In this sense the use of getAsyncState disables type inference. It can and should be avoided.

Thanks for the explanation. Let's get @mmalfertheiner on this, since I don't know all the implications of this change.