This is one of my pet peeves, so excuse me if I come across somewhat strong.

A reference is not a pointer. Conceptually, there are many similarities, but the basic use of a pointer (at least in C and assembly) is that the pointer itself can be manipulated. As far as I know, you can't manipulate references without Deep Magic. Discussions of pointer concepts are worth very little to non-C/ASM newbies learning references, and can confuse C/ASM people even more. There is nothing to be gained by bringing pointers into a discussion of references.

Now of course, I realize you weren't trying to bring pointers into a reference discussion, you just used a similar term because you're familiar with it, so I'm not attacking you for that. (I'm attacking you for saying "aren't they really the same thing" :) )

The implementation must differ because you cannot just use a bare address. If you are doing some sort of reference counting (which Perl does) then you need to have the reference modifying reference counts on the thing referred to. If you are doing some sort of garbage collection then the reference needs to be kept track of so that you can know to modify the reference if you move the underlying object from one place to another. Either way a reference is a considerably more complicated beast than a pointer.

The use is likewise different. First of all you would never be able to do games like pointer arithmetic with references since that would have to expose too much of the internal differences. Secondly pointers are an excellent candidate for all sorts of errors in languages that have them, so you need to be careful to carefully track when things are allocated and need to be destroyed. So references are both more limited and far safer.

This terminology difference is preserved across a lot of languages. If the language says it has references, they are opaque and it does garbage collection behind your back. If they claim pointers then that is up to you but you may be able to play a lot of Really Cool Tricks.

When it comes to sort, well trying to roll your own is a Really Bad Idea. The reason is trivial. Perl has a lot more overhead than a low-level language like C. Therefore if you roll your own, you have to expect to be running about 10 times slower than the native function. If you are not then that is a bug in the native function, not an excuse to start rolling your own! If you cannot accept this and keep on reinventing the wheel then your code is going to be slower and more buggy than it needs to be.

And finally, I appreciate the thought of trying to answer, but the execution is still an issue. Perl questions here, particuarly simple ones, tend to be answered fairly fast and completely. So if you don't have an answer that you are sure is accurate and complete, you probably should just wait for someone else to answer it. If nobody answers it for a bit, then give a partial answer if you have one.

I am sorry if I am coming off stronger than I intended. I just wanted to make sure that my -- vote didn't confuse you, that you understood the reason for it. As it stood your answer was one which was misleading in ways that IMO would result in someone becoming further confused. I am trying to explain why I think that, and make sure that you were not left wondering (as has happened to me in the past) why someone voted against your post.