On Sep 11, lyf said:
>hi, I am a perl beginner, and I am confused by $1.
>what does $1 ($2,and so on) mean?
>and how to use them?
The $DIGIT variables correspond to sets of ()'s in a regex. Here's an
example:
$pn = "1-800-555-1212";
if ($pn =~ /^\d-(\d)\d{2}-(\d{3}-\d{4})$/) {
print "toll free\n" if $1 eq '8';
print "main number: $2\n";
}
This would print:
toll free
main number: 555-1212
Each $DIGIT is related to the DIGITth set of capturing parentheses in a
regex. The first set of () sets $1, the second set of () sets $2, and so
on.
For more information, read:
perldoc perlrequick
perldoc perlretut
perldoc perlre
--
Jeff "japhy" Pinyan [EMAIL PROTECTED] http://www.pobox.com/~japhy/
RPI Acacia brother #734 http://www.perlmonks.org/ http://www.cpan.org/
** Look for "Regular Expressions in Perl" published by Manning, in 2002 **
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