proposal #4095: add Applicative instance for Either

Yitzchak Gale gale at
Tue May 25 12:22:34 EDT 2010

Ross Paterson wrote:
> The proposal is to add this instance to Control.Applicative:
>    instance Applicative (Either e) where...
> compatible with the usual Monad instance.

+1 for this Applicative instance

-1 for the orphan Monad instance with the silly
superclass constraint that this Applicative instance
is meant to extend

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