in reply to japhy has met his match

Ok, updated AGAIN, thanks to MeowChow pointing out the obvious. ;) 
        123456789_123456789_123456789_123456789_123456789_123456
$re = q{^.*(??{$&ne'^.*(??{'.substr($re,7,-4).'})\z'&&'(?!)'})\z};

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japhy -- Perl and Regex Hacker

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Re: Re: japhy has met his match
by MeowChow (Vicar) on May 25, 2001 at 21:05 UTC
    Am I missing something? 
      print 
   q|^.*(??{                                    })\z| =~
   m|^.*(??{$&ne'^.*(??{'.substr($&,7,36).'})\z'})\z|

  # outputs 1

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    Update to japhy's update: In that case, why not simply: 
      $re = q{^.*(??{$&ne$re&&'(?!)'})\z};

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       MeowChow                                   
               s aamecha.s a..a\u$&owag.print
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Re: Re: japhy has met his match
by Masem (Monsignor) on May 25, 2001 at 20:39 UTC
    Close, but not quite yet:

    First, here's a 5.005 version that's the same thing: 

    $regex = '^(.*)(?(?{my$x=substr$1,9,-4;$1ne"^(.*)(?(?{$x}))\\z"}))\z';

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    And here's the stinger: 
    $test  = '^(.*)(?(?{my$japhy;my$x=substr$1,9,-4;$1ne"^(.*)(??{$x}))\\z
+"}))\z';

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    (Mind you, I'm playing with this on 5.005, and things that I don't expect to match are matching - I wonder if there's a bug in the RE engine at this point. However, I'm pretty sure that adding any text prior to "my$x..." will still match...)

    I think that you need to specify the exact length of the substr that you're looking at, which means to just simply do some character counting.

    Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain
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