G'day sidmuchrock,

I looks like you might be working with CSV data. If that's the case, Text::CSV already does what you want (if you also have Text::CSV_XS installed, it will run faster). Text::CSV also solves many other issues you might encounter with CSV data; e.g. fields containing the separator character, such as 800,900,"1,000". Unless you're doing this as a purely academic exercise, this really isn't a wheel you should be reinventing.

Here's a quick example. I used your posted data and added a bit more to show some features, including: just one, zero-length element; and the embedded separator character I showed above.

#!/usr/bin/env perl

use strict;
use warnings;

use Text::CSV;

my $csv = Text::CSV::->new();

while (my $row = $csv->getline(*DATA)) {
    # Do something with all elements, e.g.
    print 'Elements: ', 0+@$row, '; Last: |', $row->[-1], "|\n";
}

__DATA__
1,,3,4,,,
1,,3,4,,,not_empty

,
800,900,"1,000"
[download]

Output:

Elements: 7; Last: ||
Elements: 7; Last: |not_empty|
Elements: 1; Last: ||
Elements: 2; Last: ||
Elements: 3; Last: |1,000|
[download]