When should One Use r-value References and noexcept

With the introduction of move semantics into C++ one has to decide when and how to use it for the benefit. I have already written on the problems that it introduces. Also I came up with a clear rule for this:

• If you store and keep an object - just use a value (no references) as a parameter. It'll handle both r-values and l-values correctly. This is the clear advantage that move semantics has given us.

• You can use copy-and-swap idiom. But there are subtleties with container like objects - you don't want unnecessary copies.

• In other cases you'll end up using either a universal reference or two overloaded methods (with r-value and l-value references as parameters).

Now to the question of noexcept. I've already written on the subject of exceptions and where to use them. With regard to noexcept my experience tells me that we should just forget about noexcept. The only case it is necessary is for std::vector or other containers ( noexcept on move constructor ). But this is the result of the really dubious decision to allow exceptions on copy and move. We should just ban exceptions in that cases and make our lives better. bad_alloc? Yes, memory allocation failure is a no-go situation. We write programs with an assumption that an OS will behave as documented. No spurious failures are allowed! No threads should become suddenly suspended, no memory allocation failures in case we're not out of memory, which is a bug of a program than a normal situation. STL went the wrong way with its exception safety paranoia. So I think one should not normally use noexcept. Try to make your constructors (all three types, rule of five) and probably assignment operators noexcept by default and allow exceptions in every other case.