
Very +1
Just yesterday I was hoping to have a (Monad m, Monoid w) => Monoid (m w)
instance; that's probably not possible because it conflicts with too many
things, such as the Monoid w => Monoid (Maybe w) instance, but having
Monoid w => Monoid (IO w) would have solved my problem. Specifically, this
was really useful for me with Foldable, because it allows foldMap to work
in a monad; I've had to define my own `foldMapM` several times already.
-- Andrew
On Thu, Nov 13, 2014 at 7:32 AM, Alexander Berntsen
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I've been waiting for this for a while.
+1. At least until someone presents downsides that I've been overlooking.
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