map -package:containers -package:ghc -package:conduit -package:bytestring -package:charset -package:monoidal-containers -package:invertible -package:os-string package:hedgehog 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.