RE: empty-directory predicate, native implementation

[Drew Adams]

> > Sorry I'm coming to this late.  It's a long thread,
> > and I've only checked your patch, not the messages.
> >
> > I don't understand why we would do this.  Is the
> > real aim to be able to have an empty-directory
> > predicate, i.e., to be able to see if there are
> > no files in a directory?
>
> I would just like to add to the previous mail; that this optimisation
> really does not matter on very first call...

Believe me, I'm not trying to second-guess any
implementation.  I haven't (and won't) look at the
C code, and I'm not very qualified to do so anyway.

I was guessing that COUNT = 1 would be quicker for an
emptiness check than COUNT > 1 (e.g. COUNT = 80000).

But my argument wasn't about implementation or
efficiency.  Even if, for some reason, C had to "get"
(info about) all of the files in the directory, just
to determine whether the dir is empty, my argument
would be the same wrt Lisp: have a separate predicate,
or have a Boolean new parameter, instead of having a
COUNT new parameter.