Re: default instance for IsString

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 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 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

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