foldlCU :: UA b => (a -> b -> a) -> a -> Chunked chsz b -> a
foldlCU f init (CU arrs) = foldl' (foldlU f) init arrs
foldlCU :: UA b => (a -> b -> a) -> a -> Chunked chsz b -> a
foldlCU f init (CU arrs) = foldl' (foldlU f) init arrs
foldlCU f init (CU arrs) = foldl' (foldlU f) init arrs