Hello,

I am using « negative lookbehind » pattern matching, and I get a very strange result.

Here is the simple code:

use strict;
use warnings;

my $s = '"toto"';
if ($s =~ /^(?<!\\)"(((?<=\\)"|[^"])+)(?<!\\)"$/) {
  print "It matches!\n";
  print $1 . "\n";
  print $2 . "\n";
}

[download]

And this is the result:

It matches!
toto
o

[download]

????

Where does the « o » come from ?

Any idea ?

Best regards

Denis

In reply to negative lookbehind and VERY strange capture by Denis.Beurive

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