Is it that important that there be only one variable for the entire application? Why not just

sub f {
    our $OnceOnly{+__LINE__} ||= (log(...),1);
}

[download]

which would, ISTM, be largely equivalent (and somewhat simpler), but with no risk of warnings?

In reply to Re: Why do I get a "used only once" warning here? by Porculus
in thread Why do I get a "used only once" warning here? by rovf

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