Condiments.kt

abstract class CondimentDecorator: Beverage() {
    abstract override var description: String
}

class Soya(var beverage: Beverage): CondimentDecorator() {

    override fun cost(): Double {
        return beverage.cost() + 1.0
    }

    override var description = beverage.description + ", Soy"
}

class Mocha(var beverage: Beverage) : CondimentDecorator() {

    override var description = beverage.description + ", Mocha"

    override fun cost(): Double {
        return beverage.cost() + 0.5
    }

}