enabling evaporation of overlays

[Katsumi Yamaoka <yamaoka@xxxxxxx>]

Hi,

This message is continued from the following thread:

n05yv0h3.fsf@ID-23066.news.dfncis.de">http://thread.gmane.org/n05yv0h3.fsf@ID-23066.news.dfncis.de

>>>>> In [emacs-w3m : No.06589] Katsumi Yamaoka wrote:

> I also got a report from Hiroshi Fujishima yesterday that there
> is a problem in Gnus.  When a user types the `t' key in the
> summary buffer, mouse-face spreads over the whole article header.
> It is required that the value for gnus-treat-buttonize-head is
> `head' (which is the default).  I haven't investigated it yet,
> though.

The problem arises since it is the middle of the development of
overlay functions in the Emacs CVS head.  It can be fixed by the
following code:

(eval-after-load "gnus"
  '(progn
     (defun gnus-make-overlay (&rest args) "\
Run `make-overlay' and enable the `evaporate' property on overlay."
       (let ((overlay (apply 'make-overlay args)))
	 (overlay-put overlay 'evaporate t)
	 overlay))
     (require 'byte-comp)
     (byte-compile 'gnus-make-overlay)))

It is useful that all overlays made by Gnus will be vanished
when `erase-buffer' is performed.  However, currently I don't
want to install it to Gnus CVS.  Because it doesn't affect
overlays made for widget buttons and we are unable to abolish
the gnus-kill-all-overlays function.  Furthermore, I heard
Masatake YAMATO is planning to enable evaporation of all
overlays by default.  All problems will be solved if it is
realized.

Regards,
-- 
Katsumi Yamaoka <yamaoka@jpl.org>