How to reduce redundant code when adding new c++0x rvalue reference operator overloads

Question

I am adding new operator overloads to take advantage of c++0x rvalue references, and I feel like I\'m producing a lot of redundant code.

I have a class, tree

Answer 1

Just a quick late answer: If the class in question is moveable, the move is very cheap, and you would always move from all the arguments if you can, then passing the arguments by value might be an option:

tree operator +(tree      a, tree      b);

If tree is moveable and an rvalue ref is passed as the actual argument, then the arguments to the function will be initialized with tree's move constructor where possible, else the copy constructor. Then, the function can do whatever it wants with its arguments in the appropriate way (like, say, moving their internals around).

It does incur an extra move when passing an rvalue reference argument compared with the lots-of-overloads version, but I think it's generally better.

Also, IMO, tree && arguments should maybe accept lvalues via a temporary copy, but this is not what any compilers currently do, so it's not very useful.