"Best" way of passing in a big struct to a function?

[Val Markovic]

> This whole topic is a bit of a thorny one in that D's design is 
> trying to
> avoid some of the problems that allowing const T& to take 
> rvalues in C++
> causes, but it makes a situation like what you're trying to do 
> annoying to
> handle. And auto ref doesn't really fix it (even though that's 
> whole the reason
> that it was added), because it only works with templated 
> functions. There have
> been some discussions on how to adjust how ref works in order 
> to fix the
> problem without introducing the problems that C++ has with it, 
> but nothing has
> actually be decided on yet, let alone implemented.

So if I don't need to support accepting rvalues, is there an 
argument for "in ref" over "const ref"? "in ref" looks superior: 
it's more descriptive and from what the docs say, it gives even 
more guarantees about the behavior of the function.