in reply to Best way to extract RE backreferences

Here's a handy shortcut: 
my ($b, $c, $d) = ($str =~ /(b)(c)(d)/);

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If a match is done in list context it returns a list of the backreference matches.

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Re: Re: Best way to extract RE backreferences
by Fletch (Bishop) on Feb 05, 2003 at 19:51 UTC

    Strictly speaking the parens around the match itself aren't necessary; it's already in list context. 

    % perl -le '$_="abcde";my($z,$y,$x)=/(b)(c)(d)/;print "$x$y$z"'
dcb

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    However if you wanted to save only a subset of the saved subexpressions, the ()'s around the match will let you use brackets to get a slice (but then you might be better off using non-capturing parens instead).

    my( $y, $x ) = (/(b)(c)(d)/)[1,2];
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[d/l]
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      However if you wanted to save only a subset of the saved subexpressions, the ()'s around the match will let you use brackets to get a slice (but then you might be better off using non-capturing parens instead).

      <nit>Maybe. You might have a large parsing regex that's been compiled with /o and you want the 3rd through 9th columns of 12 columns.</nit>

      ------
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        Your objection is valid but you shouldn't be using /o anymore. We have qr() now.

        Makeshifts last the longest.

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