Empty VS null array?

[Meta]

On Friday, 18 October 2013 at 21:15:32 UTC, H. S. Teoh wrote:
> Yes, but if you declare a variable to contain a set, then by 
> definition there is *something*, even if it's an empty set.

Exactly. There is still *something*, even though the set is 
empty. That is, the set itself.

> For there to be nothing, there shouldn't even be a variable in 
> the first place. The fact that the variable exists and has an 
> identifer means that there is *something*. So your argument is 
> moot.

Not really. Null is a special marker to indicate the absence of a 
value. There is nothing, as opposed to the previous case.