map -package:containers -package:dlist -package:conduit -package:basement -package:case-insensitive -package:monoidal-containers -is:exact -is:exact -package:aeson -package:charset -package:os-string -package:integration -package:text -package:ghc package:Cabal-syntax is:exact

map f xs is the list obtained by applying f to each element of xs, i.e.,
map f [x1, x2, ..., xn] == [f x1, f x2, ..., f xn]
map f [x1, x2, ...] == [f x1, f x2, ...]
>>> map (+1) [1, 2, 3]
[2,3,4]