Delegation Pattern `by` Kotlin

Main.kt

interface Car {
    fun carMethod();
}

interface Bus {
    fun busMethod();
}

class Leyland : Bus {
    override fun busMethod() {
        println("Bus method")
    }
}

class BMW : Car {
    override fun carMethod() {
        println("Car method")
    }
}

class Combination(c: Car, b: Bus) : Car by c, Bus by b

fun main(args: Array<String>) {
    val busPlusCar = Combination(BMW(), Leyland())

    busPlusCar.busMethod()
    busPlusCar.carMethod()
}