Re: C API question

[Roberto Ierusalimschy <roberto@...>]

> > That is a good question. Since userdata got "environments" in 5.1
> > (called uservalues, in 5.2), the need for luaL_ref diminished a lot.
> >
> > -- Roberto
> >
> Not so much that it is going to be removed I hope, how else would C code
> keep a reference to Lua data without generating its own id mechanism?

For a fixed number of references there are several ways (e.g., unique
strings or addresses of C static variables). For dynamic creation of new
references there are several ways, too. One is to use a lightuserdata
as a key, as Mark suggested. (If the refered object is a userdata, its
address is a perfect key.) Another is to use your own table inside
the registry to keep only your references. (This table may be weak,
solving the GC problem.)

-- Roberto