mark value classes as scala 2 only

[bishabosha]

No description provided.

[sjrd]

Value classes are still a thing in Scala 3. Implicit value classes are typically replaced by extension methods, but not other value classes.

[bishabosha]

Value classes are still a thing in Scala 3. Implicit value classes are typically replaced by extension methods

We did plan before in #2812 to promote users to use opaque types in Scala 3, and we also decided in #2768 how to label pages intended to be promoted to scala 2 users.

There's nothing on the page that says it's forbidden to use value classes in Scala 3, the intention is to recommend something else as idiomatic.

Edit: I added a comment to #2812 to include your suggestion

, but not other value classes.

the other value classes are supposed to be replaced by a combination of opaque types and extension methods