FizzBuzz in Swift

fizzBuzz.swift

func fizzBuzz(num: Int) -> String {
    switch num {
    case _ where num % 15 == 0:
        return "FizzBuzz"
    case _ where num % 3 == 0:
        return "Fizz"
    case _ where num % 5 == 0:
        return "Buzz"
    default:
        return num.description
    }
}

for num in 0...20 {
    print(fizzBuzz(num))
}