I see a few things, here.

First, you should always use:

use strict;
use warnings;
use diagnostics; # not everyone puts this in but I think it's helpful

[download]

But that's just general stuff. The big question I have is why use a while (especially with the -- eesh -- next statement) when an if is really what you want? Rewriting this using your (excellent) suggestion of the reformulated for: 

foreach my $pdu_num (3 .. 8) 
{
        $pdu_num = 11 - $pdu_num unless defined $order;
        if (my $node = shift @nodes)
        {
                $map{$node} = $pdu . '['.$pdu_num.']';
        }
}

[download]

gives, I think, a much clearer chunk of code

--
Wade

In reply to Re: More effective way to increase two elements of a list in parallel? by wade
in thread More effective way to increase two elements of a list in parallel? by et_alia

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