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in reply to Re: 'grouping' substrings?
in thread 'grouping' substrings?

I dont know whether using $& is effecient or not.

Using $& is not efficient, and usually to be avoided. See the entry in perlvar for details.

Update: perhaps I was a bit imprecise. I'd say something that "imposes a considerable performance penalty on all regular expression matches" is inefficient, but I guess it depends on what type of inefficiency we're talking about.

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Re^3: 'grouping' substrings?
by ikegami (Patriarch) on Feb 01, 2006 at 16:52 UTC

    That's not exactly true. $& is only inefficient if you have another regexp in your program which doesn't capture.

    However, it's use is discouraged, since captures can perform the same task without the "effect at a distance" of $&.

    In this case, just replace $& with $1, and you're set.