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On 17-May-06, at 10:50 AM, Roberto Ierusalimschy wrote:

Suppose I'd like to keep references to a bunch of lua_Objects that
were passed to my C function by Lua. The reference manual (no pun
intended) says that lua_ref() will obtain a reference to the
lua_Object that's on top of the stack, but does this apply for the
"getting arguments" situation? In other words, is this the right way
to obtain references to passed arguments (for later use), or am I way
off? In the likely event that I'm "way off" -- how is this done

void my_Lua_callable_function()
  int ref_to_param_1 = lua_ref(1);
  int ref_to_param_2 = lua_ref(1);

  // etc ...

This way is fine. If you need to use these parameters in the same function after building their references, then you may prefer to copy thm to the stack top (with lua_pushobject) and then call lua_ref. But if all you want
is to build the references, your code is quite Ok. (Except that the
signature of your function should be int foo (lua_State *L), and you
should pass this 'L' when calling lua_ref...)

Well, I forgot to mention that I'm using Lua 3.1 (it's forced by my target platform, can't upgrade). In this case, I think the prototype for a Lua callable C function is "void fun(void)", right?

-- Roberto