map -package:Cabal -package:base -package:text -package:bytestring -package:blaze-html -package:unordered-containers is:exact -package:vector package:io-streams

Maps a pure function over an InputStream. map f s passes all output from s through the function f. Satisfies the following laws:
Streams.map (g . f) === Streams.map f >=> Streams.map g
Streams.map id === Streams.makeInputStream . Streams.read