I haven't payed much attention to how much of type families is/should be implemented for 6.8.2. What of equality constraints? The following parses alright, but can't be used it seems.
------------------------------------ module Foo where class C a where proof :: a instance (a ~ Int) => C a where proof = 1 ------------------------------------ %> ghci -fglasgow-exts -XUndecidableInstances Foo.hs GHCi, version 6.8.2: http://www.haskell.org/ghc/ :? for help Loading package base ... linking ... done. [1 of 1] Compiling Foo ( Foo.hs, interpreted ) Ok, modules loaded: Foo. *Foo> proof :: Int : panic! (the 'impossible' happened) (GHC version 6.8.2 for i386-unknown-mingw32): nameModule $dC{v aoz} Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug ------------------------------------ I would follow that last advice if I knew this was *supposed* to work. :-) Cheers, /Niklas _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users