Of course, it should have been 0 or 1 not 0 or many.

I don't see any advantage in using /msx, nor \A & \z for this?

(Nor qq{} when simple quotes do, but that a personal beef. PBP has a lot to answer for :)

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
RIP an inspiration; A true Folk's Guy

In reply to Re^3: conditional regex by BrowserUk
in thread conditional regex by Anonymous Monk

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