The point is is that you should make sure that transforms like:

```case q"$mods class $name(..$args) { ..$body" => q"$mods class $name(..$args) { ..$body"```

Don't introduce any new members. This invariant holds for regular classes but would introduce garbage constructor for classes created manually outside of the parser. We might want to add another syntactic construct for situations like that that will have it's own parsing rules and handling.