[Haskell-cafe] Newtype deriving with functional dependencies

Louis Wasserman wasserman.louis at gmail.com
Sun Feb 1 22:06:19 EST 2009

Is there any sensible way to make

newtype FooT m e = FooT (StateT Bar m e) deriving (MonadState)

work to give instance MonadState Bar (FooT m e)?

That is, I'm asking if there would be a semantically sensible way of
modifying GeneralizedNewtypeDeriving to handle multi-parameter type classes
when there is a functional dependency involved, assuming by default that the
newtype is the more general of the types, perhaps?

Louis Wasserman
wasserman.louis at gmail.com
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