Where is monadic fold right?

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#1

Hi,

Data.Foldable contains foldM which does monadic fold left. Haskell foldable package has functions for both ways.

Is the conventional workaround to do input reverse and use foldM?
For a random access array it is not the most efficient way.

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#2

I think foldrM is much more useful in a lazy language than a strict one. But no, if I needed a right fold to incorporate monadic effects, I would just use foldr: foldrM f z = foldr (\x y -> f x =<< y) (pure z)

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