How do I specify a default value for a function ty...

# getting-started

[Benoît Liessens]

How do I specify a default value for a function type parameter?
e.g. I want to make the action parameter optional by giving it a default "no-op" value

fun move(predicate: (Node<T> -> Boolean), action: (Node<T> -> Unit)) {
   // body
}

[Benoît Liessens]

ok, got it

fun move(predicate: (Node<T>) -> Boolean, action: (Node<T>) -> Unit = { (T) -> Unit }) {
 // body
}

[ephemient]

you could write

fun move(predicate: (Node<T> -> Boolean), action: (Node<T>) -> Unit = { })

just like in ordinary code you could write

val action: (Node<T>) -> Unit = { }