Is it possible to "overload" based on visibility?

[60rntogo]

On Friday, 25 September 2020 at 14:21:59 UTC, Steven 
Schveighoffer wrote:
> in does not mean "take by reference", it means "scope const"

I'm not sure that I really understand scope, but I read 
https://dlang.org/spec/function.html#param-storage as saying "in 
means take by value or reference depending on what is better 
optimized". Is that not what we want here?

> It depends on if you want to return a copy. If you want to 
> return a reference if the source is a reference, use auto ref 
> on the return as well. But if you still want to protect the 
> internal data, it would have to be const.

Right, again I'm wondering if there is a way of saying "just 
figure out if it's more optimal to return by value or const 
reference".