On Wed, Dec 16, 2009 at 10:40 AM, haskell@kudling.de wrote:

1) Is the way i define and use "SubSet", the only/valid way to define subsets?

2) What's the best way to make "doSomethingElse" polymorphic?

I'm not very familiar with them, so I'm not sure if it's totally applicable, but generalized algebraic datatypes (GADTs) might be what you're looking for. -- Jeff Wheeler (Sorry, sent this to the author originally.)