[nXML-mode related]Q: How was modeline-process handled in XEmacs(was Re: Is there a working nxml-mode in XEmacs?)

[It's me FKtPp ;)]

hi all,

first, status report for the porting work progress.

I've done some dirty work on porting the font-lock related code to
XEmacs, and it looks like I successed.  nXML-mode's font-lock code do
not relay on font-lock-keywords, and it's fully self contained.  So the
work is much easier than we thought of, I wrote some wrapper function
s(details please find out from 
http://hg.linuxfire.com.cn/nxml-mode-fktpp/rev/d9127044a849 ) for exist
#'nxml-fontify-* and It just works. ;)

second, same as the mail-subject said.

How is 'modeline-process get processed when redisplay(forced) modeline?
nxml-mode used to setup a 'mode-line-process with a list:

(setq mode-line-process '(rng-validate-mode (:eval
(rng-compute-mode-line-string))))

which will update modeline major-mode status string whenever modeline
got redraw. But it seemd that it is not the case of XEmacs, I've also
tried the same way by the following code:

  (setq modeline-process
    `(rng-validate-mode ,(rng-compute-mode-line-string))))

The result is ... only the *FIRST* *TIME* value returned by #'
rng-compute-modeline-line-string get displayed in the modeline, 
modeline never changed at following #'redraw-modeline call.

So, the question is... How is 'modeline-process get handled in XEmacs?
It's contents(list) just get evaluated once upon changeing the
'modeline-process? or will be evaluated whenever modeline get redraw? Is
there a way to emulated FSF behavior?