[Dn_Ab]

It's worth noting that Reifeid generics also have their limitations. I believe Haskell also does a similar level of erasure. Reified generics makes it harder to include higher order types and so the level of abstraction in Scala's collections or monad transformers would be much harder without type erasure. Haskell's type system is better at keeping the annoyance of erased types away by not just casting every thing to a top type.