Userdata example for 5.2.2

[Garthy <garthy_aul@...>]

Hi,

Is there a complete example for LUA 5.2.2 that shows setup, creation, 
method definition, and garbage collection on userdata, similar to the 
example here:

http://lua-users.org/wiki/UserDataExample

The linked example won't work with 5.2.2, as it lacks "luaL_openlib" at 
least. Digging around suggests you have to rewrite it to use 
"luaL_setfuncs" "carefully". This is a bit difficult if you're not 
already familiar with the API. Is there a good example of this?

Cheers,
Garth