And that'd totally break down as soon as some underlying class does something you didn't expect. C++ RAII patterns and Rust's ownership systems are required for

And that'd totally break down as soon as some underlying class does something you didn't expect. C++ RAII patterns and Rust's ownership systems are required for a very good reason (that the GC sidesteps but also makes all code dependent of), the NVec further up in the thread works because it's an explicit abstraction.