Lists, but with an
Applicative functor based on zipping.
Examples
In contrast to the
Applicative for
List:
>>> (+) <$> [1, 2, 3] <*> [4, 5, 6]
[5,6,7,6,7,8,7,8,9]
The Applicative instance of ZipList applies the operation by pairing
up the elements, analogous to
zipWithN
>>> (+) <$> ZipList [1, 2, 3] <*> ZipList [4, 5, 6]
ZipList {getZipList = [5,7,9]}
>>> (,,,) <$> ZipList [1, 2] <*> ZipList [3, 4] <*> ZipList [5, 6] <*> ZipList [7, 8]
ZipList {getZipList = [(1,3,5,7),(2,4,6,8)]}
>>> ZipList [(+1), (^2), (/ 2)] <*> ZipList [5, 5, 5]
ZipList {getZipList = [6.0,25.0,2.5]}