On Sun, May 31, 2009 at 7:10 PM, Manuel M T Chakravarty <[email protected]> wrote: > Lee Duhem: >> >> On Sat, May 30, 2009 at 7:35 PM, Maurí cio <[email protected]> >> wrote: >>> >>> Hi, >>> >>> How do I include type families (used as associated >>> types) in a module export list? E.g.: >>> >>> class MyClass a where >>> type T a :: * >>> coolFunction :: Ta -> a >>> (...) >>> >>> If I just include MyClass and its functions in the >>> list, instances in other modules complain they don't >>> know T, but I wasn't able to find how (where) to >>> include T in the list. >>> >> >> In export list, you can treat 'type T a' as normal type declaration, ie, >> write >> T(..) in export list. > > There is also special syntax to export associated types. You can write > > MyClass (type T) > > in the export list; cf, > > http://haskell.org/haskellwiki/GHC/Type_families#Import_and_export >
This is a better way. lee _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
