Re: [Haskell-cafe] Supplying a default implementation for a typeclass based on another class

2009/2/28 Lennart Augustsson :

If you were writing your own Binary class you could simply make Show and Read superclasses of Binary and it would be trivial to have default implementations based on Show and Read.

That's my fallback approach, yes, but I don't really want to make Binary a subclass of Show,Read. I'd like to be able to define this for classes in packages I *don't* control, and without *requiring* the fallback to work.. As you say, it isn't exactly a critical issue. I was just wondering if it was possible, really.