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in reply to Negative expressions with alternation in ProxyRemoteMatch

Try negative look ahead.

my @str = qw/ a.jpg b.gif c.png d.txt e.jpeg a.jpg.3 /;

for my $str (@str) {
  if ($str =~ /.*?\.(?!gif|jpe?g)/) {
    print "matched: $str\n";
  }
}

__END__

# output is
matched: c.png
matched: d.txt
matched: a.jpg.3

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Re^2: Negative expressions with alternation in ProxyRemoteMatch
by redhotpenguin (Deacon) on Aug 30, 2005 at 07:21 UTC
    Thanks for the help, this is what I was trying to do. Works great, and it makes sense that the '?!' (whabang?) is at the start of the alternation.
[reply]
      An alternative is to use negative look behind... Your code was actually negative look ahead. To look behind, you need the < directive.

      /(?<!\.gif)(?<!\.jpg)(?<!\.jpeg)$/

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[reply]
[d/l]

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