Dan Doel wrote:
What do I have to import to get the Functor ((,) a) instance?
(Of course, I can define it myself, but this is not the point.)
In GHC 6.6 and above, you'll need to import Control.Monad.Instances (a bit of
a weird place to put it, but I guess there's no Control.Functor and such
On Wednesday 19 September 2007, Janis Voigtlaender wrote:
> Hi,
>
> the Prelude docs found via
>
> http://haskell.org/hoogle/hoodoc.cgi?module=Prelude&name=Functor&mode=class
>
> claim that there is an instance
>
> Functor ((,) a)
>
> And yet, I get (in GHC, but similarly in Hugs):
>
> Prelude> fma
Hi,
the Prelude docs found via
http://haskell.org/hoogle/hoodoc.cgi?module=Prelude&name=Functor&mode=class
claim that there is an instance
Functor ((,) a)
And yet, I get (in GHC, but similarly in Hugs):
Prelude> fmap (+1) (undefined,2)
:1:0:
No instance for (Functor ((,) a))
arisi
