Hi rsriram,

Here is one way to do it. But If you have proper xml file it is always good to use XML modules.

use strict;
use warnings;

my $string = '<nl><item>asdfasdf</item><item>asdfasdf</item></nl><nl><
+item>asdfasdf</item><item>asdfasdf</item></nl>';

$string =~ s|<nl>((?:(?!</nl>).)*)</nl>|'<nl>'.&item($1).'</nl>'|egs; 

print $string;

sub item
{
    my ($item) = @_;
    
    my $no =1;
    
    $item =~ s/<item>/'<item num="'.$no++.'">'/egs;     
    return $item; 
}

output:
-------
<nl><item num="1">asdfasdf</item><item num="2">asdfasdf</item></nl><nl
+><item num
="1">asdfasdf</item><item num="2">asdfasdf</item></nl>
[download]

or even shorter than the above

$string =~ s|<nl>((?:(?!</nl>).)*)</nl>|my $item = $1; my $no = 1; $it
+em =~ s/<item>/'<item num="'.$no++.'">'/egs;"<nl>$item</nl>"|egs;
[download]