Yes, I think type families are here to stay. There is no formal policy about GHC extensions. Generally speaking, I regard GHC as a "laboratory" in which to test ideas, which militates in favour of putting things in so that people can try them. Once in they are hard to take out again (linear implicit parameters is a rare exception) because some come to rely on them. If there's anything in particular you need, ask. The main thing that is scheduled for an overhaul is the "derivable type class" mechanism, for which Pedro is working on a replacemement. Simon | -----Original Message----- | From: glasgow-haskell-users-bounces@haskell.org [mailto:glasgow-haskell- | users-bounces@haskell.org] On Behalf Of Permjacov Evgeniy | Sent: 10 December 2010 19:42 | To: glasgow-haskell-users@haskell.org | Subject: Type families status | | Is it safe to consider type families and associated type families | extensions for ghc as stable ? Wich related extensions (flexible | contexts, undecidable instanses and so on) may be deprecated or changed | in near (2-3 years) future and wich may not? | | _______________________________________________ | Glasgow-haskell-users mailing list | Glasgow-haskell-users@haskell.org | http://www.haskell.org/mailman/listinfo/glasgow-haskell-users