Re: creating a table in C

[Tomas Guisasola Gorham <tomas@...>]

	Hi Shea

On Thu, 1 Feb 2007, Shea Martin wrote:

> int l_creat_player( lua_State* vm )
> {
> 	lua_newtable( vm );
> 
> 	int address = (int)&gSomePlayer;
> 
> 	lua_pushstring( vm, "id" );
> 	lua_pushinteger( vm, address );
> 	lua_settable( vm, -3 );
> 
> 	//Now I would like to add a function to this:
> 
> 	lua_pushstring( vm, "get_mojo" );
> 	lua_pushcclosure( vm, l_player_get_mojo, 0 );
> 	lua_settable( vm, -3 );
> 	return 1;
> }
> 
> I register the function as get_player;
> 
> My l_player_get_mojo() is like this:
> 
> int l_player_get_mojo( lua_State* vm )
> {	
> 	lua_getfield( vm, -1, "id" );
> 	int address = lua_tointeger( vm, -1 );
> 	Player* p = (Player*)address ;
> 	lua_pushnumber( vm, p->GetMojo() );
> 	return true;
> }
> 
> My script is:
> 
> player = get_player()
> print( "mojo is " .. player.get_mojo() )
> 
> The code dies on getting the "id" field, as the stack does not seem to
> have the table on the top of the stack.
> 
> I think my problem is how I add the "member function" to the player table.
	Don't you have to call the function with the argument?
Something like: player:get_mojo() ?  I think it should be better
to check for the argument.  For that, see the luaL_check* functions.
Or better, you should consider using a full userdata instead of a
table.  You could set its metatable to store the function and use
the __index to retrieve it.  Take a look at Roberto's book!

	Regards,
		Tomás