G'day FloydATC,

Perhaps something like this would be more to your liking: 

$ perl -Mstrict -Mwarnings -le '
    my @vlans = (2, 3, 4, 7, 10, 11, 12, 20);
    my $last = $vlans[0] - 2;
    my @ranges;
    push @{$ranges[$#ranges + ($_ - $last > 1)]}, $last = $_ for @vlan
+s;
    print join ",",
        map { $_->[0] == $_->[-1] ? $_->[0] : join "-", @{$_}[0, -1] }
+ @ranges;
'
2-4,7,10-12,20

[download]

-- Ken

In reply to Re: Converting a list of numbers to use a range operator by kcott
in thread [Solved] Converting a list of numbers to use a range operator by FloydATC

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