Cross posting here, in case anyone has some advice: https://kotlinlang.slack.com/archives/C1H43FDRB/p1683656637745809

What you can just do is have

Success

exist standalone as a sealed interface, and then use the normal

Result

class, and deal with the different types of success using a

when

on the actual value inside of the Result (because what's the point of treating a failure as a

Result<SuccessType1>

Vs a

Result<SuccessType2>

)

The success type is predetermined on invocation though. So doing the when on the success types would be redundant -- both from the compiler's pov but also from the coder's pov

As in you get a

Result<SuccessType1>

instead of a more general

Result<Success>

?

Yep, exactly. There would be a handful of different successes in the grand scheme of the codebase, but when it's being used the result will be only be a Failure or a specific Success

Do you really even need a sealed hierarchy then? Just use the real values for success. You won't need to create new result types cuz you'll just use the stdlib one, and you won't need to unwrap further (because you can go with the most basic hierarchy datatype, and you'll just get the value out of (kotlin's)

Result

with no further wrappers

One more constraint on that note -- I also want the Result class to implement Android's

Parcelable

Hmmmm, you could use something like Arrow's

Either

, or if you really want the

value class

performance, then just copy the Result source code and make it additionally parcelable (although note that that will box)