in reply to
How does next label work?
I’m of the opinion that this sort of thing is the very worst kind of “Perl Golf” ... a game with all water-traps and no tee. The construct is intended to go directly to the next iteration of a “real loop” as designated by the specified label-name. If you are caught using it where no such loop exists (in the eyes of your co-workers, not Perl), and even if it so happens that Perl’s compiler accepts it, then you nevertheless richly deserve to be designated the one who gets to clean the coffee maker for the next full year.
(Urgh: you do clean the coffee maker, don’t you??)