Re: Type of userdata

[Dirk Laurie <dirk.laurie@...>]

2012/1/12 Luiz Henrique de Figueiredo <lhf@tecgraf.puc-rio.br>:
>> Is there any way to find out from Lua what the registry type of a
>> userdata is, short
>> of giving it a `type` method?
>
> If you used luaL_newmetatable to assign a metatable to the udata,
> then you can search the registry for an entry whose value is that
> metatable. The key is then the "type" you seek.
>
> This example print "FILE*":
>
> t=getmetatable(io.stdin)
> for k,v in pairs(debug.getregistry()) do
>        if v==t then print(k) end
> end
>
>

Aha!  Thanks!