Proposal: merge either into transformers

[Mario Blažević]

On 12-12-07 04:44 AM, Roman Cheplyaka wrote:
> I propose to add the sole module of the 'either' package[1],
> Control.Monad.Trans.Either, to the transformers package.

+1. Then I can drop the EitherFunctor type from the monad-coroutine package.