Re: C API - lua_next traversal of "array" table

[Philipp Janda <siffiejoe@...>]

Am 20.08.2016 um 10:04 schröbte Tim Hill:
> > On Aug 19, 2016, at 11:50 AM, Ross Berteig <Ross@CheshireEng.com> wrote:
> >
> > Since you already need to iterate, then iterating until nil saves you the additional O(log n) cost from `#t`.
>
> Yet again, #t and iterating t to the first nil rears it’s ugly head.

If `t` contains a sequence, then the first `nil` you'll encounter is 
also the only `nil`, and marks the end of the sequence. So it actually 
conforms to the definition of `#` (ignoring metamethods for the moment). 
Additionally, it also has defined behavior (however useful it might be) 
if `t` does not contain a proper sequence. It also allows you to handle 
sequences that change their sizes during iteration, and it is cheap to 
do in C code. So this approach seems like a reasonable option given the 
current state of things.

> —Tim

Philipp