But you can only use aliasing like that if you use a global variable. Of course in 5.6 you could immediately turn around with our and make it lexical, but accessing lexicals is faster than globals. (Of course we are quibbling at speed at this point, I believe the hash lookups are slower than either by a good margin.)

As for refcounting being garbage collection, yes. But there is no real garbage collector per se.

And interpreted language is somewhat semantic. Certainly you don't compile binaries. Certainly you don't interpret sourcecode directly. But the opcodes are run through an interpreter, and that causes a lot of overhead. And there is this nice thing called "eval" which is associated with interpreted langauges...