Apologies, I should have taken a closer look. It seems that the only response to this proposal came in January 2021: https://mail.haskell.org/pipermail/libraries/2021-January/031116.html I seem to remember some more discussion, probably elsewhere, but I can't find it right now. Am Mi., 30. Juni 2021 um 14:30 Uhr schrieb Dominik Schrempf :

Actually, following your link, I cannot find any discussion of the original question about foldr1' or foldl1'. The discussion goes on about enhancing the documentation of Data.Foldable. Please let me know if I missed something!

Dominik

Simon Jakobi via Libraries writes:

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This was discussed in December 2020: https://mail.haskell.org/pipermail/libraries/2020-December/031010.html

Am Mi., 30. Juni 2021 um 12:49 Uhr schrieb Ignat Insarov :

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Hello.

I notice that in `"base" Data.Foldable` there are strict left and right folds, but no corresponding folds without base case, that is, `foldl1'` and `foldr1'`. Can this omission be ameliorated? The implementation is trivial. _______________________________________________ Libraries mailing list Libraries@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries

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On Wed, 30 Jun 2021, Ignat Insarov wrote:

How about adding said functions into something like `Data.Foldable.Unsafe` then?

What is unsafe about them? "Partial"? But then it is better to have them total and in Foldable1. Maybe the old discussion was about Foldable1?

On Thu, Jul 01, 2021 at 12:01:51AM +0500, Ignat Insarov wrote:

Whichever floats your boats folks. I am a user of Haskell and I require strict folds without base case. Further I dare not meddle.

To what sort of structure(s) are looking to apply a strict foldl1? Since there is no `foldl1'` class method to override, no structures have a specialised definition. Therefore, a "default" definition can be written outside the class: foldl1' :: Foldable t => (a -> a -> a) -> t a -> a foldl1' f = fromMaybe (errorWithoutStackTrace "foldl1': empty structure") . foldl' f' Nothing where f' ma x = Just $! case ma of Nothing -> x Just a -> f a x Which means you can just use this in your own code, it need not first land in the Data.Foldable module for you to make use of it. -- Viktor. P.S. FWIW, apologies if I am misreading the tone of your message, but it does sound "demanding" to me. GHC is a free community project with no large corporation invested in its development, all the contributors want to help users, but this is easier to help users who are considerate of those to would volunteer their time to help.