`in` parameters made useful

[IGotD-]

On Tuesday, 25 August 2020 at 14:43:45 UTC, Atila Neves wrote:
>
> I think that having `in ref` is preferable than introducing new 
> rules. Everything else makes sense to me, but it's possible I'm 
> missing something.

I think that the proposal from Mathias LANG meant that 'in' shall 
not be accompanied with any other qualifier. How the parameter is 
passed is up to the compiler, if it is by value, reference or 
something else.

If you explicitly want a reference you use 'ref' just like today.