Strange use of => ?

I found this on the internet to convert an IPv4 address (w.x.y.z) to
a decimal number.

w * 16,777,216 + x * 65,536 + y * 256 + z = decimalNumber

I then found the subroutine, ip2dec in the script below.

The script works, that's not my problem. The problem is "How does it
work"? 

The "split /\./" I understand. I've looked at perldoc pack and sort of
see it is taking the ip4 address, packing it up and then unpacking.

But what's with these "=>" things? How is that routine meant to read?


TIA


Owen

========================================================
#!/usr/bin/perl

use strict;
use warnings;

my $Originator = '127.0.0.1';

$Originator = ip2dec($Originator);

my $stored = 'stored';
$stored = "$stored$Originator";

sub ip2dec {
    return unpack N => pack CCCC => split /\./ => shift;
}

print "$stored\n";            
========================================================        
-- 


Owen

• Strange use of => ? by Owen
• Re: Strange use of => ? by Jim Gibson