You cannot avoid using (??{ $code }) in a meaningful way. You need recursion, which means you either use (??{ $code }), or (?{ $code }), with the latter solution being more complicated.

Of course, if you don't have to restrict yourself to regexes, it's trivial to avoid (??{ $code }). if ($str eq reverse $str) will do.

In reply to Re: palindrome using regular expressions by Anonymous Monk
in thread palindrome using regular expressions by szabgab

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