Weak Lists?

Michael Chermside mcherm at destiny.com
Wed Jan 16 13:39:16 EST 2002

>> I would like a weak list -- a list in which the values are held with 
>> weak links.
> <snip>
>> For those who might be interested, I want this because I am creating a 
>> tree, with something sort of like this:
>> <snip>
>> ... and I thought it would be nice to let the structure clean up without 
>> having to invoke the circular reference garbage collector.
>> Fair enough, but shouldn't the childNodes list be strong references and the 
> parent be a weak reference? That way you won't need a list of weak 
> references and the tree will tidy itself up as soon as you release the 
> ultimate parent.

Actually, I didn't think it mattered whether the uplinks or the 
downlinks were the weak ones. In either case, you have the same number 
of weakref's...

Oh <slaps forehead> of course! If I implemented as I described, then 
everything but the root of my tree would disapear! So it's the uplinks 
which should be weak, not the downlinks.

-- Michael Chermside

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