Better branding of -betterC

[Ola Fosheim Grøstad]

On Friday, 30 October 2020 at 14:24:43 UTC, Steven Schveighoffer 
wrote:
> I think D was looking at one point to be able to do this, but 
> via a specialized library hook.
>
> The difference between RC and a tracing GC is that cycles can 
> prevent garbage from being detected in RC, whereas tracing can 
> find those.
>
> Even in swift, you have a notion of weak references that get 
> auto-nullified when the target gets destroyed, and not properly 
> setting up an ownership relationship will result in items not 
> being collected. But certainly it's much easier than the 
> Objective-C requirements.

*nods* Yes, you need weak references. I did like your idea of 
having reference counting and using the current GC-collection 
infrastructure for detecting cycles and dangling pointers. I 
think dynamic sanitizers can be very powerful.

Class objects are already quite heavy as each interface adds 
another pointer to each object, so I don't think adding two 
counters would make a catastrophic difference.

I once made a prototype refcounting scheme in D with borrowing 
that tracked the number of borrows at runtime. You could even add 
tracking of __FILE__ and __LINE__ and get good debug tracking 
during testing.

So there are interesting possibilities without "throwing out 
everything". E.g. retaining key properties of the tracing GC for 
development and drop down to ARC at release.