... does this leading "undef" really do anything?

It does nothing. It is a compulsive programming tick akin to
    my $scalar = undef;
    my @array = ();
    my %hash = ();
In the latter two cases, I can barely see some occasional justification for the practice because it may relieve the onerous burden of having to write a comment like
    my @ra;  # this array will remain empty until something is put into it
Otherwise...

Give a man a fish:  <%-{-{-{-<

In reply to Re: Questions about curious idiom seen in package by AnomalousMonk
in thread Questions about curious idiom seen in package by SimonSaysCake

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