I have a regex that matches parts of a date and then sticks the matches into $year $month and $day variables. In stead of using the standard $1, $2, $3 variables I wanted to play with embedding perl code into the regex.

The regex works just great on a single pass. If I stick the regex in a sub and access it more than once, then the $year,$month and $day variables only get filled on the first time it is accessed. Here is code:

#!/usr/bin/perl
use Data::Dumper;
use strict;
#use re 'debug';

my  $foo_year = "2004-11-12 12:40:42";

test($foo_year);
test($foo_year);
test($foo_year);

sub test {
  my ($date) = @_;
  print $date,"\n";
  my ($year,$month,$day);
  $date =~ m/
    (\d+)  (?{ $year  = $^N })
    -
    (\d+)  (?{ $month = $^N })
    -
    (\d+)  (?{ $day   = $^N })
  /x;
  print "$year-$month-$day\n";
}

[download]

It seems like $^N isn't getting set on subsequent calls to the regex.

In reply to regex and embedded perl code by neybar

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