map -package:containers -package:insert-ordered-containers -package:ghc -package:invertible -package:conduit -package:basement -package:filepath -package:base 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.