No instance for (Monad ((->) Integer))

Chad Scherrer chad.scherrer at gmail.com
Mon Feb 5 15:10:48 EST 2007


On 2/5/07, Neil Mitchell <ndmitchell at gmail.com> wrote:
> Hi Chad,
>
> > Prelude> let fs = [(+2), (*4)]
> > Prelude> :t fs
> > fs :: [Integer -> Integer]
> > Prelude> :t sequence fs
>
> I think you need to import Control.Monad.Instances to get the
> appropriate instance in scope.
>
Hmm, that's weird. The instance
Monad ((->) r)
is mentioned in Control.Monad, so I thought importing it might be enough.


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