$ip =~ m/^\d+\.\d+\.\d+\.\d+$/

If you're worried about a valid IPv4 dotted-decimal IP address, take a look at Regexp::Common::net (and at Regexp::Common to see how to invoke said module). And I'm sure there are other, similar CPAN resources available.

Give a man a fish:  <%-{-{-{-<

In reply to Re: COVID-19 data analytics, cryptography, and some things you should know by AnomalousMonk
in thread COVID-19 data analytics, cryptography, and some things you should know by tachyon-II

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