[Haskell-cafe] Trying to avoid duplicate instances

[Bulat Ziganshin]

Hello Eric,

Tuesday, May 13, 2008, 10:16:48 PM, you wrote:

> -fallow-overlapping-instances doesn't convince GHC.  Is there a way
> around this other than manually writing out all the instances I want?

afaik, no. typeclasses are not the same as OOP classes. i suggest you
to look into http://haskell.org/haskellwiki/OOP_vs_type_classes and in
particular papers mentioned at the end - one describes implementation
of type classes and other emphasize differences between t.c. and
classes. these should shed the light :)


-- 
Best regards,
 Bulat                            mailto:Bulat.Ziganshin at gmail.com