With a negative look ahead assertion:

$_ = "cat dog";

print 'match' if /^(?!cat)/;
print 'no match' unless /^(?!cat)/;

[download]

Prints:

no match

[download]
DWIM is Perl's answer to Gödel

In reply to Re: Regex negative word by GrandFather
in thread Regex negative word by zer

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