What is arrow-idiomatic way to return typed error ...

# arrow

[Nick Kleban]

What is arrow-idiomatic way to return typed error from function that returns Unit?

[Youssef Shoaib [MOD]]

Raise<ErrorType>.myFun(): Unit

[Nick Kleban]

Thank you. One more question - If I use either{ } in a function that returns Either<Error, Unit>, do I need to bind Unit or something?

[simon.vergauwen]

It's the safest option to use Raise directly, you can also use Either<ErrorType, Unit> but then you need to make sure to always call bind. There is a detekt plugin to check that.

[simon.vergauwen]

Yes, you need to make sure to call bind on Either<Error, Unit>, otherwise you'd swallow/ignore to error.

Or, recover using getOrElse, etc.

[simon.vergauwen]

That's why Raise<ErrorType>.myFun(): Unit is safest, you can call it inside either<ErrorType, Unit> { myFun() } but you don't need to call bind.

Raise<ErrorType> gives you the exact same API as you get inside either<ErrorType, Unit> { }, but Either is perfectly valid if that's what you're using everywhere in your project ☺️ If it's a private function you could still consider Raise IMO.

[Nick Kleban]

Thank you very much, got it