Kotlin is great, but it is a fairly heavy dependency if all you want is extension methods. Java has mostly caught up in many other aspects, so I'm experimenting with Java + one or two compiler hacks. Checked exceptions are my next target...
If it's just about ignoring forced exception management, Lombok provides the @SneakyThrows annotation.
I would need something more before I add a new type of extension. Maybe if you could solve the null-check issue.
i.e. rewriting
var x = a.getFoo()?.getBar() var x = a.getFoo() != null ? a.getFoo().getBar() : null
https://github.com/manifold-systems/manifold/tree/master/man...