Re: Replace selective-display in Gnus

[Dan Nicolaescu]

Reiner Steib <address@hidden> writes:

  > On Sat, Aug 29 2009, Stefan Monnier wrote:
  > 
  > >> Could someone propose a patch how to use invisible overlays here?  It
  > >> should be compatible with Emacs 21 (and up) and XEmacs 21.4 (and up)
  > >> if possible.
  > >
  > > Here is the gnus-sum.el code I'm using nowadays.
  > 
  > Thanks.
  > 
  > > IIRC it's not 100% correct (the behavior is not quite the same as
  > > the current one).
  > 
  > What is the difference?  (I don't use this feature so I'll probably
  > won't notice it.)
  > 
  > > This includes unrelated changes, and uses remove-overlays which was
  > > new in Emacs-22.
  > 
  > As we need the old code for compatibility with older Emacsen, I think
  > I will install it with some (fboundp 'remove-overlays) conditionals.

Instead of conditionals you could replace `remove-overlays' calls with
something like:

    (dolist (ov (overlays-in from to))
      (when (overlay-get ov 'gnus-sum)
        (delete-overlay ov)))))

which should work everywhere.