:: (a -> b -> c) -> [a] -> [b] -> [c] package:numeric-prelude

zipWith generalises zip by zipping with the function given as the first argument, instead of a tupling function. For example, zipWith (+) is applied to two lists to produce the list of corresponding sums:

>>> zipWith (+) [1, 2, 3] [4, 5, 6]
[5,7,9]

zipWith is right-lazy:

zipWith f [] _|_ = []

zipWith is capable of list fusion, but it is restricted to its first list argument and its resulting list.

Zip two lists which must be of the same length. This is checked only lazily, that is unequal lengths are detected only if the list is evaluated completely. But it is more strict than zipWithPad undefined f since the latter one may succeed on unequal length list if f is lazy.