RE: Unique object references

["Jerome Vuarand" <jerome.vuarand@...>]

Chris wrote:
> Is there any way to get a state-wide unique reference to any 
> particular object in the state?
> 
> I know there is the luaL_ref stuff but that's only unique to 
> a specific table.  I'm looking for something that can return 
> a unique reference (eg. memory pointer or something) to any 
> object in the entire state.  Something that doesn't change 
> and always refers to the same object.
> 
> I don't necessarily need to get a unique reference for basic 
> types but I would like to get them for functions and tables.  
> rawequal must be using something similar to what I am talking 
> about.  I see it is using
> some garbage collector pointer or something like that.   Is there
> currently a way to pull that out as a lightuserdata or some 
> other way to get that unique reference?

I think you can use tostring to get a unique string identifier to any
Lua value. You can also put a reference to the values you're interested
in in the registry, which is unique per Lua master state (use luaL_ref
and luaL_unref with LUA_REGISTRYINDEX as second parameter).