foldl is:package

Composable, streaming, and efficient left folds This library provides strict left folds that stream in constant memory, and you can combine folds using Applicative style to derive new folds. Derived folds still traverse the container just once and are often as efficient as hand-written folds.

Not on Stackage, so not searched. incremental folds

Not on Stackage, so not searched. Statistical functions from the statistics package implemented as Folds.

Not on Stackage, so not searched. Transducers for foldl folds.

Not on Stackage, so not searched. Attoparsec and foldl-transduce integration.

Not on Stackage, so not searched. Exception handling with FoldM