An esoteric Kotlin feature I stumbled across: <htt...

# announcements

[nwillc]

An esoteric Kotlin feature I stumbled across: https://medium.com/@nwillc/kotlin-class-inherits-from-function-675c71e04ecb

[Michael de Kaste]

sight just cuts off for me and doesn't show any more beyond

[tseisel]

The fact is that function types such as (Foo) -> Bar are in fact compiled to an actual interface: Function1<Foo, Bar> (for functions with one parameter). There are a lot of equivalent interfaces matching the number of parameters: Function0, Function2 ...
Because those are all interfaces, then yes, a class can implement them!
That's useful when you need to pass a lambda to a function and maintain some state.

[David Eriksson]

@Michael de Kaste Paywall crap? Use incognito browser

[streetsofboston]

https://kotlinlang.org/docs/reference/lambdas.html#function-types