I'm not quite sure what needs to be accomplished here. Consider the following code. Note that within a regex, you can use a $var in place of a fixed regex. s/$find/$replace/;

In general I think you will discover that:
1) regex is better than pack/unpack (except for specific cases where you know that columns are guaranteed to line up - and even then just use regex to skip columns and use list slice to get what you want. Of course pack/unpack are necessary when editing binary files, but in general this is not the right way to go.

2)indexed variables are almost never necessary in Perl. One magic thing of Perl is it reduces the probability of "off by one errors"

3)prefer foreach (@array){..} over any kind of C style for loop. I write one C style for loop per about 5K lines of Perl.

#!usr/bin/perl -w
use strict;

while (<DATA>)
{
   my $last_first_digit = ($_=~ m/(\d)\d*\s*$/)[0];
   # print "$last_first_digit\n";     #for debugging
   print "<exML LOLZ = \"$last_first_digit\"/>\n";
}

__DATA__
HAI WORLD Times 0
HAI WORLD Times 1
HAI WORLD Times 2
HAI WORLD Times 3
HAI WORLD Times 4
HAI WORLD Times 5
HAI WORLD Times 6
HAI WORLD Times 7
HAI WORLD Times 8
HAI WORLD Times 9
HAI WORLD Times 10
HAI WORLD Times 11
HAI WORLD Times 12
HAI WORLD Times 13
HAI WORLD Times 14
HAI WORLD Times 15
HAI WORLD Times 16
HAI WORLD Times 17
HAI WORLD Times 18
HAI WORLD Times 19
HAI WORLD Times 20
HAI WORLD Times 21
HAI WORLD Times 22
HAI WORLD Times 23
HAI WORLD Times 24
HAI WORLD Times 25
==============
this prints:
<exML LOLZ = "0"/>
<exML LOLZ = "1"/>
<exML LOLZ = "2"/>
<exML LOLZ = "3"/>
<exML LOLZ = "4"/>
<exML LOLZ = "5"/>
<exML LOLZ = "6"/>
<exML LOLZ = "7"/>
<exML LOLZ = "8"/>
<exML LOLZ = "9"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "1"/>
<exML LOLZ = "2"/>
<exML LOLZ = "2"/>
<exML LOLZ = "2"/>
<exML LOLZ = "2"/>
<exML LOLZ = "2"/>
<exML LOLZ = "2"/>

[download]
I think you just need to get the right regex to feed a simple loop and that will do what you want.

In reply to Re: Function call in regex replacement string by Marshall
in thread Function call in regex replacement string by PoorLuzer

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