Comment by mrweasel

That might be it, but I wondered about that one, as well as the append complaint. It seems like the author disagree with scoping rules, but they aren't really any different than a lot of other languages.

If someone really doesn't like the reuse of err, there's no reason why they couldn't create separate variable, e.g. err_foo and err_foo2. There's not no reason to not reuse err.