broken Monad Either instance?

[Christian Maeder]

Yes, thanks, this works and is worth knowing.
It looks a bit ugly but is shorter than making a new monad.

Prelude Control.Monad.Identity Control.Monad.Error>
   runIdentity . runErrorT $ fail "bla" :: Either String ()
Left "bla"

C.

Am 30.11.2011 11:39, schrieb Erik Hesselink:
> ErrorT from mtl still has a 'fail' implementation that returns a Left.
>
> Erik