Re: Is Lua used as a data representation language?

[Marc Balmer <marc@...>]

Am 08.01.2013 um 18:10 schrieb Roberto Ierusalimschy <roberto@inf.puc-rio.br>:

>> On Tue, Jan 8, 2013 at 5:31 PM, Ashwin Hirschi <lua-l@reflexis.com> wrote:
>>> It doesn't seem to handle a simple case like:>
>>>        while 1 do end
>> 
>> OK, thanks - I'll try to close some more gaps.  The approach here is
>> static checking, unlike the runtime limits Roberto suggests.
> 
> Another runtime aproach is this:
> 
> function loaddata (data)
>  local f = assert(loadstring("return (" .. data .. ")"))
>  local count = 0
>  debug.sethook(function ()
>    count = count + 1
>    if count >= 2 then error"cannot call functions" end
>  end, "c")
>  local res = f()
>  count = 0
>  debug.sethook()
>  return res
> end
> 
> It only allows expressions (no variables, no assignments) and disallows
> any kind of function calls.
> 
> -- Roberto
> 


that's kinda sweet...