Use Enumeration in Switch Statements in Swift

Written by Team Kodeco

In Swift, you can use enumerations in switch statements to match the different cases of the enumeration. This is a powerful feature that allows us to handle different cases of an enumeration in a clean and readable way. Here is an example of a switch statement that uses an enumeration of TrafficLight:

enum TrafficLight {
  case red, yellow, green
}

let trafficLight = TrafficLight.yellow

switch trafficLight {
case .red:
  print("Stop")
case .yellow:
  print("Caution")
case .green:
  print("Go")
}
// Output: "Caution"

You can also use the where clause to match specific conditions for certain cases. Here is an example of a switch statement that uses the where clause to match specific values of associated values:

enum Shape {
  case square(side: Double)
  case rectangle(width: Double, height: Double)
  case circle(radius: Double)
}

let shape = Shape.square(side: 2.0)

switch shape {
case .square(let side) where side > 2:
  print("Large square")
case .square(let side) where side <= 2:
  print("Small square")
case .rectangle(let width, let height):
  print("Rectangle with width \(width) and height \(height)")
case .circle(let radius):
  print("Circle with radius \(radius)")
default:
  print("Unexpected Shape")
}
// Output: Small square