map -package:containers -package:Cabal-syntax -package:dlist -package:base-compat-batteries -package:basement -package:monoidal-containers -package:base-prelude -package:invertible -package:bytestring -package:hedgehog -package:pipes -package:imports -package:text -package:psqueues -package:vector -package:conduit package:vector-stream

Map a function over a Stream
Map a monadic function over a Stream
Execute a monadic action for each element of the Stream
Apply monadic function to each element and drop all Nothings