Weak references.

[Jason House]

Sean Kelly wrote:

> == Quote from Jarrett Billingsley (kb3ctd2 at yahoo.com)'s article
>> "Sean Kelly" <sean at invisibleduck.org> wrote in message
>> news:fttd02$1mp1$1 at digitalmars.com...
>> >
>> > Are these tables AAs?  And how do the weak references store their
>> > reference?
>> > The type information provided to AAs is a bit weak, and so some
>> > non-pointer
>> > data is currently still scanned by the GC.  I'm going to improve this a
>> > bit in the
>> > next Tango release, but it still won't be perfect (because the compiler
>> > doesn't
>> > provide enough info for it to be).
>> In my tests I've just been doing
>> auto weakref = new WeakRef!(A)(new A);
>> and then checking that after doing god-knows-what to try to get it to
>> collect that instance of A, so it's not even that I'm doing anything that
>> crazy.
> 
> Just for kicks, try querying the GC to determine whether the GC thinks
> weakref contains pointers.
> 
> 
> Sean

How would one do that?