Tip #6 from the Basic debugging checklist... B::Deparse

use strict 'refs';
my $str = 'foo:bar:';
my($a, @options) = split(/:/, $str, 0);
my($b, $c, $d) = split(/:/, $str, 4);
use Data::Dumper;
print Dumper([$a, \@options]);
print Dumper([$b, $c, $d]);
[download]

Notice how the 2 split lines have different LIMIT values (0 and 4).

when assigning to a list, if LIMIT is omitted (or zero), then LIMIT is treated as though it were one larger than the number of variables in the list