Nested enums

enum Icecream {
   enum Flavour {
      case chocolate
      case vanilla
   }

   enum Toppings {
      case sprinkles
      case none
   }
   case flavour(Flavour)
   case toppings(Toppings)
   case none
}

The enums do not need to be defined inside Icecream, if you want to use them outside of Icecream as well.

E.g. maybe Flavour is shared across enum Icecream and enum Cake. So you would define it once globally, and not inside enumIcecream.

Then you should be able to access it like this:

let icecream: Icecream = .flavour.chocolate