DIP77 - Fix unsafe RC pass by 'ref'

[via Digitalmars-d]

On Sunday, 12 April 2015 at 07:17:07 UTC, Walter Bright wrote:
> On 4/11/2015 4:33 AM, "Marc =?UTF-8?B?U2Now7x0eiI=?= 
> <schuetzm at gmx.net>" wrote:
>> http://wiki.dlang.org/User:Schuetzm/scope3#.40safety_violations_with_borrowing
>
> A quick read of this suggests it is doing the Rust model of 
> only one mutable reference at a time. Is this really viable 
> with D?

I think it is. You have to keep in mind that this is opt-in; it 
only applies to `scope` variables. I would agree that as a 
default, it wouldn't fit D at all. I think that, for all its 
usefulness, it'd be a tad too limiting for my taste if I were 
forced to use it everywhere. In Rust, it needs to be ubiquitous, 
because their goal is to get by without a GC. We on the other 
hand just want a way to make the GC easier to avoid. We also want 
to be able to use these different programming styles side by 
side, therefore an opt-in solution is good.

Besides, I too want to recommend the article Matovitch linked to, 
and Yehuda Katz' article mentioned therein, because they make a 
good point demonstrating that it gives more correctness 
guarantees than just memory safety:

http://forum.dlang.org/post/ttjzihuffrdlgqonqiwi@forum.dlang.org

It's a great building block for lots of nice things. In fact, 
it's quite likely the only way to get these guarantees once you 
look beyond reference counting.