in reply to
-> Is Optional ?
Yes. See the docs in perlreftut which says :-
In between two subscripts, the arrow is optional.
Non-existent; I don't have TV
Non-existent; my TV doesn't have/need a remote
Under my control; I watch alone
Under the control of whoever shouts loudest
Under the control of whoever gets it first
One of many, and the TV has a mind of its own
Results (600 votes),