Until "!0" is documented to return specifically "1" and not just "a true value", your coding is dangerous.

Sure, !0 has been 1 in every implementation of Perl (so far), but there's no doc that supports that. It's merely an artifact of implementation. "!0" could return "4" and still perfectly satisfy all external Perl docs. I see nothing in perldata or perlop to validate that !0 is precisely "1". Just "true".

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to !0 is not necessarily 1 (was Re: Secret Perl Operators: the boolean list squash operator, x!!) by merlyn
in thread Secret Perl Operators: the boolean list squash operator, x!! by Aristotle

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