<@U0E9C04JE> `var occupant: T` happens in invarian...

# announcements

[raulraja]

@Dave Leeds var occupant: T happens in invariant position and you are stating that crate: Crate<in Dog> is contravariant. If you change crate: Crate<in Dog> to crate: Crate<out Dog> or just crate: Crate<Dog> it will compile.
I'm guessing star projections are equivalent to existential types and unaffected by variance and Animal is all it can infer there based on your T : Animal constrain.

[Dave Leeds]

Thanks, @raulraja. I haven't done much with Scala, Haskell, etc, so I'm not familiar with existential types, but your description of star-projections sounds correct. My big question is: since star-projection uses the type parameter constraint as the most specific type that it can infer, why can't in-projections do the same?

[Dave Leeds]

star-projection uses Animal, but in-projection is stuck using Any?.

[Max Russek]

This does actually seem particularly odd to me, especially considering that:

fun Dog.withInProjection(crate: Crate<in Dog>) {
    val starCrate: Crate<*> = crate
    val occupant: Animal = starCrate.occupant
}

does in fact compile.

[Max Russek]

FWIW, it seems to work in Java