inspired from Qiita article http://qiita.com/sohichiro/items/76208546138ffbe4e852

sample.swift

typealias PaymentType = (Bool, Bool, Bool)
func getPayAmountEasySwitch(payment: PaymentType) -> Double {
    
    switch (payment.0, payment.1, payment.2) {
    case (true, _, _):
        return 0.0
    case (_, true, _):
        return 1.0
    case (_, _, true):
        return 2.0
    default:
        return 3.0
    }
}


enum Payment {
    case Dead, Separated, Retired, Other
}

func amount(payment: Payment) -> Double {
    
    switch payment {
    case .Dead:
        return 0.0
    case .Separated:
        return 1.0
    case .Retired:
        return 2.0
    case .Other:
        return 3.0
    }
}


func contains(names:[String]) -> Bool {
    return names.filter { $0 == "Soichiro" || $0 == "Nagao" }.count > 0
}

protocol Vehicle {
    func getSpeed() -> Int
}

struct Car: Vehicle {
    func getSpeed() -> Int {
        return 100
    }
}

struct Bike: Vehicle {
    func getSpeed() -> Int {
        return 120
    }
}

struct Bus: Vehicle {
    func getSpeed() -> Int {
        return 60
    }
}