map -package:containers -package:conduit -is:exact -package:aeson -package:basement -package:charset -package:base -package:ghc -package:filepath -package:pipes package:hedgehog -is:exact is:exact

Generates a map using a Range to determine the length. This may fail to generate anything if the keys produced by the generator do not account for a large enough number of unique items to satify the required map size.