INVARIANT
The affected type parameter or type is invariant, which means it has no variance applied to it.
© 2010–2018 JetBrains s.r.o.
Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.reflect/-k-variance/-i-n-v-a-r-i-a-n-t.html