Wish list: expanded defaulting, dependent types, reflection

Ashley Yakeley ashley@semantic.org
Sat, 29 Sep 2001 15:58:48 -0700


At 2001-09-29 09:11, Mike Gunter wrote:

>  class Add a b c where add :: a -> b -> c  
>
>There does not seem to be a way to do everything I'd like in GHC even
>in its most permissive mode (I'm using "-fallow-overlapping-instances
>-fallow-undecidable-instances".)  In particular, I'd like to use bare

You know about fundeps, right? This may help:

     class Add a b c | a b -> c where {add :: a -> b -> c;};

    

-- 
Ashley Yakeley, Seattle WA