Re: Why no pairs() for userdata, __len for tables?

[Rici Lake <lua@...>]

Sam Roberts wrote:
> On Thu, Apr 19, 2007 at 11:53:15AM -0700, Mark Hamburg wrote:
> > Except that you can't get to userdata metatables from pure Lua. But one
> > could certainly replace pairs with a C function that did this and you don't
> > need to patch the Lua sources to do it.
>
> Maybe I misunderstand "get to", but  it appears that I can access
> userdata from the io library. Is this a version thing?

You can get the metatable of a userdata if it hasn't been locked
with a __metatable key. Many of us routinely set this key, though,
in order to protect the metatable