What does this logic do? Return if we have no id ... or it's not a number ... oh, I think this is validating that we have both and they're both valid?

```perl
return unless ( $id && $id =~ /^\d+$/ ) && ( $uid && $uid =~ /^\d+$/ );
```

Technically, the parenthesis are extraneous but I think they're useful to understand what's going on.