| Couldn't we make a special case for IsString, like we do for Num, | given it's special syntactic association with OverloadedStrings?
Maybe so. It's open to anyone to make a concrete proposal. See http://hackage.haskell.org/trac/ghc/ticket/6030 which may be the same issue. Simon | -----Original Message----- | From: glasgow-haskell-users-boun...@haskell.org [mailto:glasgow-haskell-users- | boun...@haskell.org] On Behalf Of Johan Tibell | Sent: 22 April 2012 18:51 | To: Brent Yorgey | Cc: glasgow-haskell-users@haskell.org | Subject: Re: default instance for IsString | | On Sun, Apr 22, 2012 at 10:37 AM, Brent Yorgey <byor...@seas.upenn.edu> | wrote: | > I do not think this is a bug. Since type classes are open, GHC does | > not do any reasoning of the form "X is the only instance in scope, so | > I will pick that one". Other instances could be added at any time | > (perhaps in other modules). In this particular instance, GHC has no | > reason to choose the Text instance other than the fact that it is the | > only instance in scope -- that is, type inference is not enough to | > determine that the Text instance should be chosen. | > | > However, I do agree that it would be nice to have a mechanism for | > specifying default instances for arbitrary (user-defined) type | > classes. | | Couldn't we make a special case for IsString, like we do for Num, | given it's special syntactic association with OverloadedStrings? | | -- Johan | | _______________________________________________ | Glasgow-haskell-users mailing list | Glasgow-haskell-users@haskell.org | http://www.haskell.org/mailman/listinfo/glasgow-haskell-users _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users