You mean something like 'datakind' in Tim Sheard's Omega? Nothing is imminent. What I'd like to do, though, is to use data *types* at the type level, rather than reproduce the data-type declaration stuff at the kind level. Thus data Nat = S Nat | Z data Foo :: Nat -> * where Nil :: Foo Z Cons :: Int -> Foo n -> Foo (S n) My dependent-type friends tell me that the paradoxes of "* has kind *" can be dealt with, but I don't understand the details yet. But as I say, nothing is very imminent. why do you ask? Simon | -----Original Message----- | From: glasgow-haskell-users-bounces@haskell.org [mailto:glasgow-haskell-users- | bounces@haskell.org] On Behalf Of Geoffrey Alan Washburn | Sent: 06 August 2005 15:18 | To: glasgow-haskell-users@haskell.org | Subject: Inductive kinds | | | Are there any plans for inductively defined kinds in some future | version of GHC? | | _______________________________________________ | Glasgow-haskell-users mailing list | Glasgow-haskell-users@haskell.org | http://www.haskell.org/mailman/listinfo/glasgow-haskell-users