Re: setfenv on userdata???

[Chris Marrin <chris@...>]

Mike Pall wrote:

> Hi,
>
> Chris Marrin wrote:
>
> > I see in 5.1-work6 that you can now set environments not only on both C 
> > and Lua functions, but also on userdatas. But I don't see anywhere in 
> > the code where this environment is being used. What can you do with this 
> > environment? Does it get used when you make metamethod calls with this 
> > userdata? Or is it just there so it can be retrieved or something?
>
>
> http://lua-users.org/lists/lua-l/2005-04/msg00213.html

Thanks for the pointer. This brings up a question:

- I assume that luaopen_queue() is what gets implicitly called when you 
do the require "queue", right? If so, then it looks like it sets the 
environment for your test program to the environment for the queue, as 
evidenced by lua_replace(L, LUA_ENVIRONINDEX). Looking at the code for 
this, it gets the current function (which is the main lua program at 
this point?) and sets its environment to the passed table(which is the 
metatable you are constructing for queue). Doesn't that change the 
environment for the whole program?

Thanks for your help...

--
chris marrin              ,""$, "As a general rule,don't solve puzzles
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