Re: Environments

["Alex Queiroz" <asandroq@...>]

Hallo,

On 3/21/07, Eva Schmidt <es@sol-3.de> wrote:
> I want to execute a little script from another script using loadfile(). Because
> of the fact that I cannot make sure that this script doesn't contain code I
> don't want to be executed (like os.exit() or something) I tried to just allow
> certain functions using an environment like that:
>
>
>     -- create local environment for loadstring()
>     local fenv = {}
>     fenv.print = _G.print
>
>     setfenv (loadstring, fenv)
>
>     result, error = loadstring (s)
>
> With this environment it should be possible to just call the printing function
> within the chunk to be loaded. Maybe this approach is too naive -  Lua forbits
> changing the environment for the function loadstring() ;-(

    You are changing the environment of the loadstring function. You
should change the environment of the loaded function:

result = setfenv(result, fenv)

Cheers,
--
-alex
http://www.ventonegro.org/