OptionOf

typealias ~~OptionOf~~<A> = Kind<ForOption, A> Deprecated: Higher Kinded types and their related type classes will no longer be supported after Arrow 0.13.0. Most relevant APIs are now concrete over the data types available as members or top level extension functions

Inheritors

Option If you have worked with Java at all in the past, it is very likely that you have come across a NullPointerException at some time (other languages will throw similarly named errors in such a case). Usually this happens because some method returns null when you weren’t expecting it and, thus, isn’t dealing with that possibility in your client code. A value of null is often abused to represent an absent optional value. Kotlin tries to solve the problem by getting rid of null values altogether, and providing its own special syntax Null-safety machinery based on ?.sealed class Option<out A> : OptionOf<A>