RCArray is unsafe

Zach the Mystic via Digitalmars-d digitalmars-d at puremagic.com
Wed Mar 4 09:44:01 PST 2015

On Wednesday, 4 March 2015 at 07:50:50 UTC, Manu wrote:
> Well you can't get to a subcomponent if not through it's owner.
> If the question is about passing RC objects members to 
> functions, then
> the solution is the same as above, the stack needs a reference 
> to the
> parent before it can pass a pointer to it's member down the 
> line for
> the same reasons.

Yeah, or you could mimic such a reference by wrapping the call in 
an addRef/release cycle, as a performance optimization.

> The trouble then is what if that member pointer escapes? Well 
> I'd
> imagine that it needs to be a scope pointer (I think we all 
> agree RC
> relies on scope). So a raw pointer to some member of an RC 
> object must
> be scope(*).

I have a whole Reference Safety System which doesn't need 
explicit scope because it incorporates it implicitly:


> That it can't escape, combined with knowledge that the
> stack has a reference to it's owner, guarantees that it won't
> disappear.

I think you and I are on the same page.

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