open class MessageBusImpl {
  val parentBus: Any?
    get

  init {
    <this> as RootBus /*~> Unit */
    <this>.#parentBus = null
  }

  constructor() /* primary */ {
    super/*Any*/()
    /* <init>() */

  }

}

class RootBus : MessageBusImpl {
  constructor() /* primary */ {
    super/*MessageBusImpl*/()
    /* <init>() */

  }

}