Re: Pushing a UserData pointer?

[Chris Marrin <chris@...>]

Rici Lake wrote:

> ...
> > Is there another way to avoid the GC problem?
>
>
> One of us is not being clear :)
>
> You said:
>
> > This leaves the userdata on the stack, so my Object ctor fiddles with 
> > it (gives it a common metatable and refs it so it doesn't get GC'ed). 
> > Then it gets popped.
>
>
> I assumed you meant by "refs it" that you used luaL_ref to create a 
> reference to it so that it *wouldn't* be collected. Now you seem to be 
> saying that you *want* it to be collected.
>
> You could do either of those things, as Mark points out, by using both a 
> weak and a strong table with the weak table backing the strong table via 
> an __index meta
>
> But perhaps I still don't understand...

You would not be the first to accuse me of obfuscation :-)

What I failed to say is that this ref I add to the object is temporary. 
It is there long enough to pop out of all the C++ creation logic and get 
back a fully initialized object. This is then handed off to Lua as a 
global object or a member of some other table. Then the ref is removed. 
After that, I want it to be under GC control like anything else.

Sorry about the confusion...

--
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