Differences between `foldl` and `foldr`
Summary
An in-depth explanation of foldl vs foldr in Haskell, including how their grouping differs, and how laziness and strictness affect performance and memory. It covers when foldl' should be used to avoid building large thunks and how foldr can work with lazy operations and infinite lists. The article uses concrete examples to illustrate evaluation order and practical guidelines for choosing between folds.