sub some_func {
	my ($args) = @_;	

	# if $args is a scalar, then make it an array ref
	$args = [$args] unless ref $args eq 'ARRAY';

	# now process 
	foreach my $arg (@$args) {
		# do stuff
	}
}

# sample calls:
some_func($one_item);
some_func([qw(bunch of items)]);