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Re: [MacPerl] $PREMATCH Question

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Ronald J Kimball
February 3, 2016 17:55
Re: [MacPerl] $PREMATCH Question
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On Tue, Feb 02, 2016 at 08:59:44PM -0500, Jonathan Levi via macperl wrote:
> Can someone explain why the following:
> echo alphabet | perl -e '$_=<STDIN>; if (m/pha/){print $PREMATCH, "\n"}'
> yields "" instead of "al", as I expected?
> Jonathan

If you want the long name, you need to use the English module, as
mentioned near the top of perlvar <>.
For example:

echo alphabet | perl -MEnglish -e '$_=<STDIN>; if (m/pha/){print $PREMATCH, "\n"}'

Using /p and ${^PREMATCH}, as Matthew suggested, will avoid performance
penalties in longer scripts, however.


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