Should foldl' be added to the post-"Plan FTP" Prelude

Ben Franksen ben.franksen at
Sun Mar 1 22:13:10 UTC 2015

Why not?

David Feuer wrote:
> No, that is not a way now that we have FTP.
> On Wed, Feb 25, 2015 at 7:31 PM, Kazu Yamamoto <kazu at> 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?
>> That is one way but I think another way is to make foldl strict:
>> I'm tired of explaining the difference of foldl and foldl' to
>> beginners. :-)
>> --Kazu

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