Note that I do not own this code. I believe I pulled it from CPAN, and that it rightfully belongs to James MacFarlane. If this is incorrect, let me know and I'll attribute it accordingly. I couldn't find where I originally pulled it from.

Here are the relevant snippets:

#-----------------------------------------------------------------
package Node;
#-----------------------------------------------------------------
sub new
{
    my ($pkg, $ip, $mac, $hostname) = @_;
    my $obj = {};
    bless $obj, $pkg;
    $obj->IP_Address($ip);
    $obj->MAC_Address($mac);
    $obj->Hostname($hostname);
    return $obj;
}

[download]

So, from what I see above, Node->new() should be called using 4 arguments. However, when the original author used Node->new(), he did this:

        $nodeobj = Node->new($ip, $mac_address, $machine);
        push(@nodes, $nodeobj);

[download]

This only uses three arguments. And if you omit one, then it appears the values would suffer a sort of 'one off' error. But.. the code appears to work fine. What gives?

Update: Thanks all!

In reply to Would someone mind helping me understand this Perl OO code? by romandas

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