I think demorgan got the best of you here. This is "all are undefined", not "at least one undefined". You want: 
if (grep !defined($_), @hash{ qw(A B C) }) {
  # at least one undefined
}

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-- Randal L. Schwartz, Perl hacker

In reply to Re: Re (tilly) 1: Checking for defined-ness for a list by merlyn
in thread Checking for defined-ness for a list by dragonchild

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