I want to have non exhaustive when's on a sealed classes to be an error, is that possible somehow?

Only if

when

is expression, you can force this

I know that; I'm talking about inspections

yes, this is quite new inspection

yeah, Saw it

Warning would be fine; I can set warningAsErrors

There is kind of a hacky thing some folks do when they want an exhaustive

when

without necessarily writing their code such that it results in an assignment -

fun Any?.exhaustive() = Unit

when (sealedInstance) {
  ...
}.exhaustive()

not exactly the most elegant solution, but one nonetheless

I prefer just call .toString or maybe use

.javaClass

as suggested someone in sealed when issue,

Any?.exhaustive()

pollutes autocomplete

¯\_(ツ)_/¯ imo calling either of those doesn’t clearly convey intent, plus it’s very rare for me to define any extension to

Any?

, so “pollution” seems like a strong word for literally one method. I agree it’d be nice to have this as a smarter language feature, but I personally don’t see that much issue with

.exhaustive()

Yes, I completely agree, there is no good solution

You can write your own function that works like an exhaustive when. You still have to update your function if you add or remove an item from your enum, but you can throw an exception if nothing matches and at least you only have to change one place. https://github.com/GlenKPeterson/Paguro/blob/2017-09-17_Kotlin/src/main/java/org/organicdesign/fp/oneOf/Or.kt#L74

Sure I can do all that. But: there is already the intention giving a hint on it - can't it just be raised to a warning?