Note that 
if (my $node = shift @nodes)
{
    $map{$node} = $pdu . '['.$pdu_num.']';
}

[download]

is not the same as the OP's code. Your code won't process the if if the first element of @nodes is false. Better to use 

if (@nodes) {
    my $node = shift @nodes;
    $map{$node} = $pdu . '['.$pdu_num.']';
}

[download]

Unless I state otherwise, all my code runs with strict and warnings

In reply to Re^2: More effective way to increase two elements of a list in parallel? by FunkyMonk
in thread More effective way to increase two elements of a list in parallel? by et_alia

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