Re: Pushing a UserData pointer?

[Chris Marrin <chris@...>]

Rici Lake wrote:

> ...
> If you don't want to go hacking the Lua core, I have another solution...
>
> You say you're reffing the new userdata anyway; this is going to store a 
> reference in the registry. There's no magic to luaL_ref other than that. 
> So why not kill two birds with one stone?
>
> Instead of using luaL_ref to store a reference in the registry, store 
> your own reference in the registry using a lightuserdata of the  this  
> pointer as a key. Then you can push the lua object onto the stack using 
> the  this  pointer, without breaking the API and without incurring much 
> overhead (since the hash of a lud is essentially the address).

The problem with that is now I would always have a pointer to the 
userdata and it would never GC, right? When I used my own table to store 
the lightuserdata key/userdata value pair, I made the values in that 
table weak so they would get collected properly.

Is there another way to avoid the GC problem?

--
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