The regex
'ab' =~ /((\w+)(?{print defined $2 ? "\$2=$2\n" : "\$2 not defined\n"})){2}/;
outputs: 
$2=ab
$2 not defined
$2=b

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Why $2 not defined? I think, the regex here must print $2=a. Is it a bug?

In reply to A bug in Perl regex(?) by Serge314

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