@frozen public enum RealmMapChange<Collection> where Collection : RealmKeyedCollection
RealmMapChange value encapsulates information about changes to dictionaries
that are reported by Realm notifications.
.initialindicates that the initial run of the query has completed (if applicable), and the collection can now be used without performing any blocking work.
.updateindicates that a write transaction has been committed which either changed which keys are in the collection, or the values of the objects for those keys in the collection, and/or modified one or more of the objects in the collection.
case update(Collection, deletions: [Collection.Key], insertions: [Collection.Key], modifications: [Collection.Key])
The keys in the previous version of the collection which were removed from this one.
The keys in the new collection which were added in this version.
The keys of the objects in the new collection which were modified in this version.
Errors can no longer occur. This case is unused and will be removed in the next major version.