$self->ports_ordered
            Returns list of references to Verilog::Netlist::Port in the order
            the ports were declared in the module’s port list.

sub show_module_names {
     my $nl = shift;
     my $fh = shift;
     foreach my $mod ($nl->modules_sorted) {
	print $fh "  ",$mod->name,"\n";
	my @ports = $mod->ports_ordered();
	print Dumper(\@ports);
	foreach my $sig (@ports) {
	    my $net = $sig->net;
	    if ( $net->width ) {
		printf ("     %sput %s [%s:%s];\n", $sig->direction, $sig->name, $net->msb, $net->lsb,);
	    } else {
		printf ("     %sput %s\n", $sig->direction, $sig->name);
	    }
	}
     }
}

% ./v2sp  --nomissing --modules memory_mask.v 
Version : 3.110
  memory_mask
$VAR1 = [
           'Q',
           'CLK',
           'CEN',
           'WEN',
           'A',
           'D',
           'OEN'
         ];
Can't locate object method "net" via package "Q" (perhaps you forgot to load "Q"?) at ./v2sp line 183.