Re: Need help with Regex

I'm not entirely sure what you want for output because you did not show an example. But, if you just want to grab the 6th column from your input, you could use split instead of a regex:

use strict;
use warnings;

while (<DATA>) {
    my $num = (split)[5];
    print "$num\n";
}

__DATA__
*> 4.23.88.0/23     64.135.0.1                             0 1000 234 
+46164 i
*> 4.23.89.0/24     64.135.0.1                             0 1000 2014
+8 46164 i
*> 4.23.92.0/23     64.135.0.1                             0 1000 2013
+8 46164 i
*> 4.23.92.0/22     64.135.0.1                             0 1000 3018
+ 46164 i
*> 4.23.94.0/23     64.135.0.1                             0 1000 4041
+8 46164 i
*> 4.23.112.0/24    64.135.0.1                             0 1000 1018
+ 174 21889 i
*> 4.23.113.0/24    64.135.0.1                             0 1000 2018
+ 174 21889 i
*> 4.23.114.0/24    64.135.0.1                             0 1000 18 1
+74 21889 i
*> 4.36.118.0/24    64.135.0.1                             0 1000 7018
+ 174 21889 i
[download]

prints:

Comment on Re: Need help with Regex Select or Download Code

Replies are listed 'Best First'.
Re^2: Need help with Regex by ewhitt (Scribe) on Nov 13, 2008 at 09:10 UTC
Interesting. I have never seen "split" used like that before. How could I pass it a variable? Say I wanted to print "four" ? `$output = "one two three four five"; $output = (split $line)[4];` [download] Thanks!	[reply] [d/l]
Re^3: Need help with Regex by toolic (Bishop) on Nov 13, 2008 at 14:24 UTC
The parentheses around split forces it to return an array. The square brackets are used to select a single element from the array returned by split. We could either use a constant numeric value, such as 3, or we could use a scalar variable, such as `$col` to select the array item. Keep in mind that Perl arrays start at 0, not 1. So, "one" becomes array element `[0]`, and "four" is element `[3]`: `use strict; use warnings; my $col = 3; my $str = "one two three four five"; my $output = (split /\s+/, $str)[$col]; print "output=$output\n"; __END__ output=four` [download]	[reply] [d/l] [select]