map -package:containers -package:base-prelude -package:ghc -package:aeson -package:blaze-html -package:charset -package:basement -package:monoidal-containers 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.