Same for autovivification. Insane feature. Useful for some problems but causes many more.
Which is a shame, because perl5 semantics had some nice features too! But there’s only so much you can do with a structure whose foundation is so wacky.
I never understood why Perl has all these crazy features. It feels like someone going "hah it would be funny if it worked like this..." but actually really implementing it.
People always said "it's because Larry Wall is a linguist!" as if it explains anything!
You always go from "this is neat" to "...but why" quickly with perl.