[Haskell] Fundep broken in GHC 6.6
gale at sefer.org
Sun Nov 12 14:35:38 EST 2006
The following class declaration worked in GHC 6.4.
I recently upgraded to 6.6 (following Debian), and
now it is broken.
class Error e => Game b mv e | b -> mv e where
newBoard :: MonadState b m => m ()
Since MonadState has the fundep m -> b, the type
of newBoard fully specifies all of the class parameters.
And this worked fine in GHC 6.4. But GHC 6.6
The class method `newBoard'
mentions none of the type variables of the class Game b mv e
When checking the class method: newBoard :: m ()
In the class declaration for `Game'
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