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in reply to Re: Arbitrary number of captures in a regular expression
in thread Arbitrary number of captures in a regular expression

Id do something like this myself. Except id probably not use look ahead and instead would approach it a different way. (I might even follow up with some code later if i get some time.)

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$world=~s/war/peace/g

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Re^3: Arbitrary number of captures in a regular expression
by Sidhekin (Priest) on Sep 25, 2007 at 11:06 UTC

    Id do something like this myself. Except id probably not use look ahead and instead would approach it a different way.

    I was annoyed with the lookahead myself, but it's unlikely to be a big deal, and I could not at the time see any way to avoid it. After some thinking, however, I believe I see a way to avoid looking ahead more than once -- just include it in the first alternation, which is matched precisely once on a successful match (anchored to the beginning of the string, and the only alternation that can match there): 

    my (@match) = $str =~ /(?:^foo (?=(?:m \d+ )+bar)|(?<!^)\G)m (\d+) /g;

    [download]

    ... or, in the less-terse form: 

    my (@match) = $str =~
  / (?: ^foo\ (?= (?:m\ \d+\ )+bar) # overall match from ^foo
      | (?<!^) \G                   # or continue from not-^
    )
    m\ (\d+)\                       # grab each digit sequence
  /xg;

    [download]

    I think that's the best I got. Match that? :)

    print "Just another Perl ${\(trickster and hacker)},"
    The Sidhekin proves Sidhe did it!

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[d/l]
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      I dont have time to put together a working example, but what i had in mind was using while, \G and also the /gc modifier in scalar context. Maybe from that you can come up with a working example, or prove me wrong, before I get the time to do anything useful with it.

      Using the underused /gc modifier was the key point I was thinking of tho.

      Oh and to be clear I wasnt trying to say my way would be better, just different. :-)

      ---
      $world=~s/war/peace/g

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