map -package:containers -package:Cabal-syntax -is:exact -package:blaze-html -package:basement -package:insert-ordered-containers -package:monoidal-containers -package:os-string -package:base-compat -package:psqueues -package:filepath -package:ghc -package:unordered-containers -package:aeson -package:vector 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