[Haskell-cafe] instance Alternative (Either [a])

[Corentin Dupont]

Hi guys!
I'd like to implement the instance in the subject:
instance Alternative (Either [a])

However the instance in Control.Monad.Trans.Error.Error gets in the way...
I cannot use this one, it works only with Strings.
My use case is that the Either handle in the Right a final value, or else
in the Left a list of things "left to do" to compute the value.
How can I do?

Thanks!
Corentin
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20140519/7007e250/attachment.html>