Why is it `interface Comparator<T>` instead ...

# stdlib

[josephivie]

Why is it interface Comparator<T> instead of interface Comparator<in T>? Like, I know theoretically you shouldn't have to specify that the T has in variance, but in common code errors will be shown if you do something like interface Sort<in T>: Comparator<T>, saying the T in Comparator is invariant.

[ilya.gorbunov]

In JVM Comparator interface is implemented with java.util.Comparator which is invariant, that's why it's invariant in common too.