heh... "substituting certain keywords with variables"... was badly worded - what I should have said was: "substituting certain keywords with the values of associated variables"

For example, I have stuff like:

    $line =~ s/<:INCOMING:([^:>]*):?>/int($incoming * ($1 || 1))/e;
    $line =~ s/<:OUTGOING:([^:>]*):?>/int($outgoing * ($1 || 1))/e;
    $line =~ s/<:INGRESS:>/$eth1/;
    $line =~ s/<:EGRESS:>/$eth0/;
    if ($line =~ /<:RADIUS:>/) {
        foreach my $ip (@radius_ips) {
            $thisline = $line;
            $thisline =~ s/<:RADIUS:>/$ip/;
            print OUT $thisline;
        }
    }
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(I'm in the process of abstracting the keyword/value pairs into a lookup hash, as per my previous post)