question about && in declaration

[swobph11]

I sometimes found the declaration like 'int &&a', 'T &&v' in the function argument list. What's that meaning?

[Disch]

They are r-value references.

This article has a pretty good explanation:

http://www.cprogramming.com/c++11/rvalue-references-and-move-semantics-in-c++11.html

[swobph11]

Thank you very much!

[KyiannaJones]

Here's an example of a Double Address Operator:

vector&
operator=(vector&& __x) // <-- Note double ampersands here
{
// NB: DR 675.
this->clear();
this->swap(__x);
return *this;
}

Link, for additional help:

http://stackoverflow.com/questions/4549151/c-double-address-operator