menu_book Course Curriculum (Elm Complete Course) expand_more
List.foldl
Learn List.foldl in Elm with a construct-specific explanation, a unique example, a practical boundary, and a mastery check.
List.foldl is an atomic Elm topic inside Lists & Collections. The example below uses the actual construct named by the lesson rather than a generic placeholder.
Focus on what List.foldl changes: the input, binding, control path, object state, collection, runtime effect, or language contract. Then alter one value and verify that the behavior changes for a reason specific to this feature.
Topic-specific example
List.foldl (+) 0 [ 4, 5, 6 ]
Check the input collection shape, whether the operation mutates or returns a new value, and what happens for an empty collection.