Enums and Pattern Matching

Enum Cases

Enums name a small set of possible states.

Choose from named cases

enum_cases.swift 
enum Direction {
    case north
    case south
    case east
    case west
}

let input = 
var direction = Direction.east

switch input {
case "north":
    direction = Direction.north
case "south":
    direction = Direction.south
case "west":
    direction = Direction.west
default:
    direction = Direction.east
}

print("input=\(input)")
print("direction=\(direction)")

enum Direction {
    case north
    case south
    case east
    case west
}

let input = 
var direction = Direction.east

switch input {
case "north":
    direction = Direction.north
case "south":
    direction = Direction.south
case "west":
    direction = Direction.west
default:
    direction = Direction.east
}

print("input=\(input)")
print("direction=\(direction)")

enum Direction {
    case north
    case south
    case east
    case west
}

let input = 
var direction = Direction.east

switch input {
case "north":
    direction = Direction.north
case "south":
    direction = Direction.south
case "west":
    direction = Direction.west
default:
    direction = Direction.east
}

print("input=\(input)")
print("direction=\(direction)")
enum An enum case is a typed value. A switch can convert outside input into one of the known cases.