my actual use case looks more like this: {-# LANGUAGE OverloadedStrings #-} {-# LANGUAGE FlexibleInstances, TypeSynonymInstances #-}
import Data.Text as T class ShowT a where showT :: a -> String instance ShowT T.Text where showT = show instance ShowT String where showT = show main = print (showT "Hello!") Ambiguous type variable `a0' in the constraints: (ShowT a0) arising from a use of `showT' at default.hs:16:15-19 (Data.String.IsString a0) arising from the literal `"Hello!"' So I actually want to define a default instance for a typeclass I define that uses isString instances. On Sat, Apr 21, 2012 at 6:24 PM, Daniel Peebles <pumpkin...@gmail.com> wrote: > I think it'll be hard to do that without putting Text in base, which I'm not > sure anyone wants to do. > > Dan > > On Sat, Apr 21, 2012 at 8:20 PM, Greg Weber <g...@gregweber.info> wrote: >> >> I would like to default IsString to use the Text instance to avoid >> ambiguous type errors. >> I see defaulting capability is available for Num. Is there any way to >> do this for IsString? >> >> Thanks, >> Greg Weber >> >> _______________________________________________ >> 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