[ESS] Object name completion slow

[Stephen Eglen]

 >  > I have Emacs-21.3.50.1 (from http://nqmacs.sourceforge.net/) +
 >  > ESS 5.2.3 running on Windows XP and object completion is so slow that I 
 >  > go for a coffee the when I press TAB the first time after starting Emacs 
 >  > + ESS to complete an object name. (Perhaps I should never turn the thing 
 >  > off?!)
 >  > 
 >  > I had Xemacs running earlier and then object completion was much quicker 
 >  > and actually saved time :) (replaced with GNU Emacs for various reasons)
 >  > 
 >  > I am very fond of ESS and if someone with more knowledge could figure 
 >  > out the reason behind this slow behavior that would be super.

Just to confirm: on my laptop, Emacs 21.3.1 took just over 2 minutes
to show completions after first hitting tab in an *R* buffer.  For
comparison, XEmacs 21.4.13 on the laptop took just a few seconds.

Not quite sure where to start looking, but I'll start ...!

Stephen