In practice, you write out ThreatLevel.MIDNIGHT, let the IDE import it for you, and then use an IDE hotkey to do the static import and eliminate the prefix.
This is true, with the caveat that your imports don’t share member names in common (e.g. you can’t static import two “medium” members, one from SpiceLevel and the other from PizzaSize). Swift doesn’t have this restriction, at least as far as enums are concerned.
