[Haskell-cafe] Newtype deriving with functional dependencies

[Daniel Gorín]

On Feb 2, 2009, at 1:06 AM, Louis Wasserman wrote:

> 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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> Haskell-Cafe at haskell.org
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did you try this?

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