does anyone know, if kotlin has extension function like this:

any.takeIf<Int>()

You can easily roll your own:

inline fun <reified T> Any.takeIf(): T? = if (this is T) this else null

any as? Int

https://kotlinlang.org/docs/typecasts.html#safe-nullable-cast-operator

Hm, maybe

takeIf

mislead me a bit. I guess

as?

is perfectly ok. I'm using it like so:

(any as? User)?.id

I guess doing

any.takeIf<User>()?.id

doesn't really make it more readable.

I opened corresponding issue some time ago. Because I needed the extension for chained calls. But it was closed in favour of future improved contracts that will infer the result type in

.takeIf { it is MyType }

.