It would be almost a fast, use less memory (if your multi-dimensional array is sparsely populated, *much less*), and far simper to code if you use a hash with composite keys instead.

Basically, you concatenate your indices together, separated by some suitable character (I've used ';' below), and use the result as the key to a hash. That will give you the same ability to look things up by index, but will not require you to reserve space for elements you do not use.

Your entire snippet above can be reduce to the following, with the addition that it will handle any number of dimensions.

my $ranges = [
    { I => "2", },
    { I => "3", J => "2", },
    { I => "4", J => "3", K => "2", }
];

my $array; ## The name is a lie!!

foreach my $rvarHASH ( @{ $ranges } ) {
    my @rvarLIST = sort keys %$rvarHASH;
    my @orderedIndices = @{ $rvarHASH }{ @rvarLIST };
    my $array->{ join ';', @orderedIndices } = $netlist;
}
## Err...That's all folks!
[download]

It's a little worrying that your declaration my $array; is inside the loop, meaning that it will vanish as soon as you exit the loop, before you get a chance to use it--but I'll put that down to you being a non-strict person, that added a few mys to avoid the cacophony :)