Re: Lua 5 and tags

[Vincent Penne <ziggy@...>]

Alex Sandro Queiroz e Silva wrote:

> Hallo,
>
>     You can say two objects (userdata or tables) are of the same type 
> if they share the same metatable. If want to refer to your types by 
> name, you can create entries in the global namespace using the type 
> name as a key and the metatable as a value. I guess luaL_newmetatable 
> and luaL_getmetatable do just that.


Ok, I see the idea. I was not aware of these luaL functions, this is 
what I'm going to need. There is even a luaL_checkudata which does 
exactly what I want, that is checking the type of my userdata.

>     You can't associate metatables with light userdata, but they are 
> useful in other contexts. The I/O standard library stores FILE* 
> pointers in light user data.
Ok ... I can certainly see some use for them, but I suppose you have to 
be careful.

>     Now that Programming in Lua is online (http://www.lua.org/pil/), 
> it's definitely a excellent read for anyone studying Lua.


I will ! Thanks for the answer.

Vincent Penne.