I'd agree that foldl' should be in Prelude. foldr', on the other hand, is another trap. It only makes sense for left-associated data structures like snoc lists, but some may think that foldr' is an "improved" version of foldr and use it for lists as well, which would be a mistake. On 24/02/15 22:24, Bob Ippolito wrote:
I would love to have foldl' as part of the Prelude. I use it quite frequently and it seems like a beginner trap to have foldl but not foldl' (which is almost always the better choice). I see that foldMap has been added (in addition to all of Monoid and Traversable), why was foldl' left out?
It might be good measure to add foldr' as well, although I use that much less frequently.
-bob
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