next if /^\s*[#*]/; # comments start with # or *

##</code><code>##

$curroption = $1 if s/^([A-Z]+) //;

##</code><code>##

# at top of program
my @options = qw/on except some more options/;
my $opt_string = join '|', @options;
my $opt_pattern = qr/^($opt_string)\s+/i;

# instead of your line
$curroption = $1 if s/$opt_pattern//;

##</code><code>##

push @{$options{$curroption}}, split(/,\s*/);

##</code><code>##

while (my ($option, $val_ref) = each %options) {
    print "$option -- ", join (',',@$val_ref), "\n";
}