Lennart Borgman <lennart.borgman.073@student.lu.se> writes:
> Jeremy Hankins wrote:

>> I personally consider viper to be more of an implementation of vi in
>> elisp; it generally works quite well with other emacs modes without
>> interfering with their use.  There are a few exceptions, though -- I'd
>> love to get viper to work better with folding.el, for example.
>
> What version of Emacs do you use? What are the problems with folding.el?

It's the debian unstable emacs-snapshot package 20061003-1, so 22.  I'm
using folding.el v3.35, which is current, I believe.  I've hacked
folding.el a bit -- mainly to set up an option to not narrow when
folding-shift-in is called.  I've attached a patch against folding.el,
if you're interested, and I'm using this advice for viper-search:

;; This advises viper-search so that it behaves well with folding-mode.
(defadvice viper-search (around jjh/folding-viper-search activate)
  (let ((executing-kbd-macro t))
    ad-do-it)
  (let* ((start (match-beginning 0))
         (end (match-end 0))
         (match (buffer-substring start end)))
    (when folding-mode
      (folding-shift-in))
    (search-forward match end t nil)
    (goto-char start))
  (or executing-kbd-macro
      (memq viper-intermediate-command
            '(viper-repeat viper-digit-argument viper-command-argument))
      (viper-flash-search-pattern))
  ad-return-value)

It's a bit ugly, because it sets executing-kbd-macro so that it can
override the way viper-flash-search-pattern is called.  Unfortunately
this disables the message about the search wrapping the buffer, but
without it folding marks are flashed instead of the search match.  If
anyone has a better suggestion I'd be interested -- I'm pretty new to
elisp.  Ideal would be a hook in viper-search, I guess.

What I'd really like, though, is for ex-style line addressing to work
properly, but I don't really see how that's possible without significant
modifications to viper.  From what I can see it looks like viper handles
generating addresses for lines in a variety of places, and they'd all
have to be tracked down to make it behave with folding-mode.