interface Person {
    var name: String
    var age: Int
}

interface Car {
    var make: String
    var model: String
}


class ThingHolder<T : Any> {
    var thing: T? = null

    inline fun <reified P : T> thing(builder: P.() -> Unit) {
        val clazz = P::class.js
        thing = js("new clazz()").unsafeCast<P>().apply(builder)
    }
}

fun <T : Any> thingHolderBuilder(builder: ThingHolder<T>.() -> Unit): ThingHolder<T> {
    return ThingHolder<T>().apply(builder)
}

fun main() {
    thingHolderBuilder<Car> {
        thing<Car> {
            make = "Honda"
            model = "Civic"
        }
    }
    thingHolderBuilder<Person> {
        thing<Person> {
            name = "John"
            name = "Doe"
        }
    }
}