fun main(args: Array<String>) {

//make an object that makes an internal object.

val m = Master()

//call a function on the internal object that then calls

//through to the lamda function that was passed into it.

m.apprentice?.sendMessageThroughLambda()

//A similar was to pass a message to a parent object would be to

//use an interface

m.apprentice?.sendMessageThroughInterface()

}

interface PassMessageListener {

fun message(message: String)

}

class Master: PassMessageListener {

var apprentice: Apprentice?

init {

//pass in the function print to the Apprentice object.

apprentice = Apprentice(::print)

//setup the interface listener

apprentice?.passMessageListener = this

}

fun print(message: String) {

println(message)

}

//interface method

override fun message(message: String) {

print(message)

}

}

class Apprentice(send: (String) -> Unit) {

val send = send

var passMessageListener: PassMessageListener? = null

fun sendMessageThroughLambda() {

//sends directly to the function on a whole 'notha level

send("Print this for me.")

}

fun sendMessageThroughInterface() {

//traditional interface way to pass a message

passMessageListener?.message("Print this for you")

}

}