Fundep question

Gabor Greif ggreif at
Fri Jul 31 13:54:44 UTC 2015

Hi all,

say I want to instantiate

    class Dep (a :: k) b | a -> b


    instance Dep x y => Dep (Just x) (Maybe y)

Is this supposed to work? I get "The coverage condition fails" errors.

For simple cases like

    instance Dep True Bool

etc. it seems to work fine.

Thanks and cheers,


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