[kimundi]

I think they just meant that Rust references are like normal first-class generic types. Eg, you can nest them to get a &mut &T for example, since they behave more like a pointer in that regard.

C++ references on the other hand are more like modificators of a type, eg you can have a T or a T&, but having a (T&)& does not make sense. (Outside of templates, where it gets folded down to a T&.)