[Haskell-cafe] Issues(Bugs?) with GHC Type Families

Hugo Pacheco hpacheco at gmail.com
Thu Mar 6 21:30:41 EST 2008

What I said is not true since overlapping instances are not that much
Btw, in previous versions of GHC this worked well, but now I suppose order
does not suffices to define instances overlapping

How could I compile such an example, assuming that I want to use the
instance C String for Strings only and the more general instance for the

class C a where
    c :: a

instance C Char where
    c = 'a'

instance C a => C [a] where
    c = [c :: a,c :: a]

instance C String where
    c = "a"

cc = c :: String

Sorry for the newbie question.
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