Re: LUA_REGISTRYINDEX is a valid index?

[张睿 <zrui16@...>]

> 2015-02-11 5:59 GMT+02:00 张睿 <zrui16@hotmail.com>:
> > Section 4.5 of Lua 5.3 document says:
> >
> >         The registry table is always located at pseudo-index LUA_REGISTRYINDEX, which is a valid index.
> >
> > Is it correct?

> Saying that LUA_REGISTRYINDEX is a pseudo-index means
that most API functions that requires an index into the stack
will work with a pseudo-index too, e.g.

What does the last part of the sentence, "which is a valid index", mean, after all?