`in` parameters made useful

[Mathias LANG]

On Tuesday, 25 August 2020 at 14:43:45 UTC, Atila Neves wrote:
> On Friday, 31 July 2020 at 21:49:25 UTC, Mathias LANG wrote:
>> Hi everyone,
>> For a long time I've been pretty annoyed by the state of `in` 
>> parameters.
>> In case it needs any clarification, I'm talking at what's 
>> between the asterisks (*) here: `void foo (*in* char[] arg)`).
>>
>> [...]
>
> 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.

Why is it preferable ? Genuine question here.
I originally had in mind to support `in ref` as being the user 
forcing `ref` on the param. It just seemed *obvious*. However, 
after a lot of playing around with it, it wasn't that obvious 
anymore.