Feature request: Data.Foldable.asumMap

I'd like to request that an asumMap function be added to Data.Foldable, which would be a generalization of concatMap in the same way that asum is a generalization of concat. Its proposed definition:

asumMap :: (Foldable t, Alternative f) => (a -> f b) -> t a -> f b
asumMap f = foldr ((<|>) . f) empty

This is almost equivalent to a combination of asum and fmap, but it doesn't require a Functor t constraint like that does.

Notes on its usefulness:

• Here's a Stack Overflow question that asks for a function ((a -> Maybe b) -> [a] -> Maybe b) that this is a more general form of: https://stackoverflow.com/questions/19643664/standard-haskell-function-a-maybe-b-a-maybe-b
• The alternative prelude Relude includes this function (although theirs is implemented in terms of foldMap and Alt instead of foldr and <|>): https://hackage.haskell.org/package/relude-0.4.0/docs/Relude-Foldable-Fold.html#v:asumMap
• The Util library includes Util.altMap, which is just another name for this: https://hackage.haskell.org/package/util-0.1.14.0/docs/Util.html#v:altMap
• This can also be thought of as a more useful version of Data.Foldable.find. For example, if you have a sum type such as Either and want to find the value in first one of it that's Right, you could do asumMap rightToMaybe x. If you were to instead do find isRight x, the Either won't be unwrapped even though you know it's Right, so you'll then have to do something unclean (like a partial function) to get the value out.

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Adding asumMap could help offset the loss of the getFirst . foldMap (First . f) idiom due to #15028 (closed).

The usual way to get a decision on an addition to base like this one is to make a proposal on the libraries mailing list.

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