Quote class to add the following two functions
Virtual Quote * clone () const & amp; {return new Quote (* this); }
Virtual Quote * clone () & amp; & {return new Quote (STD: : move (* this)); }
Why can't the second is:
Virtual Quote * clone () & amp; & {return new Quote (* this); }
Don't function with & amp; & Limit must first convert * this to rvalue operate again?
But after changing the third formula application can run normally,
So why should the book with STD: : move (* this))?