The old use of defined @arr
is deprecated, cause the logic was broken.
For me undefined means "not initialized" (yet), like with my $a. But this state doesn't exist for array and hashes, they are initialized empty.
And if it existed it would be different from (defined and) empty.
Nevertheless undef @a is allowed, adding even more confusion:
=> (1, 2, 3, 4, 5, 6)
DB<154> undef @a
( addicted to the Perl Programming Language)
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