Re: Assigning a varable inside of (?{})

You can just use the named captures $1 and $2 to store the values (also note the warning in perlre about (?{ code }) being highly experimental).. also, no need for string references here.

use strict;
use warnings;

while (<DATA>) {
    next unless /\S/;
    my ( $sunrise, $sunset ) = get_time($_);
    next unless $sunrise && $sunset;
    printf "Sunrise is: %s Sunset is: %s\n", $sunrise, $sunset;

}

sub get_time {
  my $string = shift;
  return unless $string =~ /sunrise:\s+(\d+:\d+)\s+sunset:\s+(\d+:\d+)
+/;
  return ( $1, $2 );
}

__DATA__
Aberdeen, Scotland 57 9 N 2 9 W sunrise: 03:12 sunset: 21:08
Adelaide, Australia 34 55 S 138 36 E sunrise: 06:52 sunset: 16:41
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But where the undef was coming from was a blank line in <DATA> ... so the match failed, so $sunrise/$sunset where undef. Just a quick check for a valid string/success on the match resolves it.

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Re^2: Assigning a varable inside of (?{}) by davido (Cardinal) on May 03, 2006 at 16:18 UTC
But where the unief was coming from was a blank line in <DATA> ... so the match failed... No it didn't. Place a "or die qq/failed\n/;" after the regexp and you'll see. While the OP certanly wouldn't ever know if it did or didn't fail (because he doesn't check), when I checked, it's not failing. The real problem is a scoping issue related to when regexes are compiled. Update: I do want to congratulate you on zeroing in on the optimal solution, however. I see no good reason to be relying on `(?{...})` and `$^N`, with their inherent difficulties, just to emulate what `$1` and `$2` do automatically, and without the complexity. Dave	[reply] [d/l] [select]
Re^2: Assigning a varable inside of (?{}) by monsterzero (Monk) on May 03, 2006 at 16:32 UTC
Hello, I don't think that is the problem. If you look at the error it is in line 2. If what you say is true it would have said line 3. I believe (from the other answer) it is a scopeing issue? Anyway thanks for the reply.	[reply]