map -package:containers -package:Cabal-syntax -package:dlist -package:bytestring -package:ghc -package:charset -package:basement -package:aeson -package:imports -package:psqueues -package:regex-tdfa -package:foldl -package:insert-ordered-containers -package:blaze-html -package:text -package:invertible -package:vector -package:first-class-families -package:cql -package:hedgehog 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