R-values and const ref

[dsimcha]

== Quote from Steven Schveighoffer (schveiguy at yahoo.com)'s article
> On Thu, 09 Sep 2010 11:24:14 -0400, Eldar Insafutdinov
> <e.insafutdinov at gmail.com> wrote:
> > I agree that auto ref may be a better option here, but I still see no
> > reason to
> > disallow it. It is a performance issue, not a safety one. And as you
> > said this
> > only works for templates, virtual functions are out of the game here.
> >
> > PS. opEquals issue is very annoying, indeed.
> Yes, I forgot that you are allowed to overload via ref.  That would make
> sense for virtual functions.
> The problem with allowing const ref rvalues is then you are not *able* to
> make a better performing function, because rvalues match against const ref
> as well as the non-ref version.
> -Steve

After Bug 4843 (the one I posted this morning about overloading ref vs. non-ref w/
structs) is fixed, it might be a good idea to allow auto ref for non-templated
functions as shorthand for a ref function plus a non-ref function that binds to
rvalues and forwards to the ref function.  On the other hand this might be too
much special casing just to save a little typing.  It also might not fly w/ Walter
and other people who care about low-level/ABI stuff because it breaks the idea
that, unless something is explicitly a template, one function at source level
should map to one function at the binary level.