Re: ntemacs hangs when openning the attached file

[Alan Mackenzie]

Hi, Stefan!

On Fri, May 23, 2008 at 05:36:34PM -0400, Stefan Monnier wrote:

> > The problem was that c-neutralize-syntax-in-CPP was inefficiently
> > coded.  I've optimised it using essentially only Emacs primitives in
> > the defun's main loop.  It now runs almost 2 orders of magnitude
> > faster.

> Sounds good.

> > Eli, I'd appreciate it very much indeed if you could review this new
> > code, please - earlier versions of it were peculiarly troublesome.

> Don't know about Eli.

That's OK.  You'll do instead.  ;-)  (Thanks!)

> But here's some comments:

> > +   ;; Note: SPEED _MATTERS_ IN THIS FUNCTION!!!
> > +   ;; 
> >     ;; This function might do invisible changes.
>                              ^^
>                             make

I hereby resign from my role as project linguistic pedant.  ;-)  That one
(and ~100 others) have been in the source for ~5 years, put there by
Martin.  How could I miss this??

> > +     (setq pps-position beg  pps-state nil)

> It would be a lot more lispy to explicitly let-bind pps-position and
> pps-state here, rather than declare them earlier without initializing
> them and then initializing them here.

I'd thought that that would just be an unnecessary extra `let'.  However,
having tried it, it does make the code a bit clearer.  So yes, thank you
- I'll be doing this more in the future.

> >       (while (and (< (point) end)
> >             (search-forward-regexp c-anchored-cpp-prefix end t))
> >         ;; If we've found a "#" inside a string/comment, ignore it.
> > !       (setq pps-state
> > !       (parse-partial-sexp pps-position (point) nil nil pps-state)
> > !       pps-position (point))
> > !       (unless (or (nth 3 pps-state)       ; in a string?
> > !             (nth 4 pps-state))    ; in a comment?
> >     (setq mbeg+1 (point))
> >     (c-end-of-macro)          ; Do we need to go forward 1 char here?  No!
> > !   (c-neutralize-CPP-line mbeg+1 (point))
> > !   (setq pps-state
> > !         (parse-partial-sexp pps-position (point) nil nil pps-state)
> > !         pps-position (point))))))

> I have the impression that this second call to parse-partial-sexp is
> unnecessary.

DUH!!!  Of course!  Wake up, Alan!  That's the whole point of the call to
`c-neutralize-CPP-line', just above.  Thanks!

>         Stefan

-- 
Alan Mackenzie (Nuremberg, Germany).