Use backreferences, like this:

while (<DATA>) {
  print "match on $1\n" if /^\S+ (\d+) \S+ \1$/;
}
__DATA__
foo 1000 bar 1000
foo 1000 bar 500

[download]

--
David Serrano

In reply to Re: regex search valid only if registers n and n+1 are equal? by Hue-Bond
in thread regex search valid only if registers n and n+1 are equal? by Voronich

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