map -package:containers -package:aeson -package:basement -package:psqueues -package:conduit -package:charset -package:ghc -package:monoidal-containers -package:incipit-base -package:text -package:regex-tdfa -package:unordered-containers package:pipes is:exact

Apply a function to all values flowing downstream
map id = cat

map (g . f) = map f >-> map g