[Haskell-cafe] Idiomatic ways to make all instances of a certain class also instances of another?

[Evan Laforge]

> However, I'd be curious to know if (a) There are better or more
> idiomatic ways of achieving the same effect, and (b) Whether or not I
> should be doing this at all; It did occur to me that this seems rather
> trying to re-implement OOP-style inheritance with typeclasses, and
> therefore perhaps not a very Haskellish approach to designing

Could you give a specific example of the problem you're trying to solve?