my %values = (
	name => 'chromatic',
	rank => 'saint',
	style => 'obnoxious',
);

my %rev_values = do_something(%values);

foreach my $key (keys %rev_values) {
	print "$key => $rev_values{$key}\n";
}

sub do_something {
	my %values = @_;
	foreach my $key (keys %values) {
		print "$key => $values{$key}\n";
		$values{$key} = reverse $values{$key};
	}
	return %values;
}