You use an enumeration or an enum to define a restricted set of values.
The following code defines an enumeration for a thread state.
enum State { case Inactive case Active case Hibernate case Terminated } var machineState = State.Inactive machineState == State.Inactive ? println("Inactive") : println("State Unknown")
To define an enumeration for the alphabet while keeping track of the position of each letter in the alphabet, use the code as follows.
enum Alphabet:Int{ case A = 1 case B, C, D, E, F, G, H, I case J, K, L, M, N, O, P, Q case R, S, T, U, V, W, X, Y, Z }
To add the integer value of A to the integer value of B, use the code as follows.
let result = Alphabet.A.toRaw() + Alphabet.B.toRaw()