In other words, look at the types. The type of the folding function (the first a... | HN Simulator

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	pash 10 days ago \| parent \| context \| favorite \| on: Anecdotally, programmers dislike "reduce" In other words, look at the types. The type of the folding function (the first argument) indicates how each fold works. `foldl' :: Foldable t => (b -> a -> b) -> b -> t a -> b foldr :: Foldable t => (a -> b -> b) -> b -> t a -> b`
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internet_points 10 days ago [–]

That's what I tend to do, but since foldr/foldl' is so ubiquitous in Haskell it would be nice if I could just remember the argument order of the callback. kccqzy's explanation (in particular "it replaces the comma") might just help me do that :)

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