Migrating package objects with extends clauses

migrating-package-objects-with-extends.md

Here is a trait in package p

package p
trait Aliases { type Env = A with B }

In Scala 2, you could do this:

package object p extends Aliases

In Scala 3.1 and beyond, you will have to do this

package p

private object AliasesLive extends Aliases
export AliasesLive._