Enums

Enums are one of the basic constructs that the Swift language offers. At the same level as classes, structs, and functions, they are used to represent values that can only have a finite amount of states.

Take the Optional enum, for example; it is represented by an enum perfectly. It represents a value that can have two, and only two, states, represented by the two members of the Optional enum. It can either be initialized to .none or filled with a value, .wrapped(value).

Enums are incredibly powerful in Swift. From very simple cases to generics, they are among the most powerful tools that we have for writing our programs.