I have a basic logic question. The solution shows the predicate checking the existence of “lastupdated” and then checking to ensure it is a type string. However, I wrote the predicate to only return “lastupdated” with type string. If something is a type string, then it exists, right?
Since null is it’s own type, “lastupdated” entries that are null will still exist, but won’t match to type string.
So, do we really need ensure “lastupdated” exists and has type string, or is my method okay?