map is:exact -package:text -package:basement -package:monoidal-containers -package:imports -package:dlist -package:insert-ordered-containers -package:case-insensitive -package:containers -package:conduit -package:psqueues package:unordered-containers

Transform this map by applying a function to every value.
Transform this set by applying a function to every value. The resulting set may be smaller than the source.
>>> HashSet.map show (HashSet.fromList [1,2,3])
HashSet.fromList ["1","2","3"]