not showing expirable articles

[Dan Christensen <jdc+news@uwo.ca>]

This was discussed a long time ago, but I don't know if a good
solution was ever proposed.  I use auto-expire, or manually mark
articles as expirable.  When I've done this, I would like it if
by default such articles didn't show up in the summary buffer
(unless I enter with `C-u RET' or something like that).  And
that the expirable articles could be brought in with a keystroke
like `/ E'.

I accomplish this with the following code:

; This runs only when the summary is first prepared, and not after
; other limiting commands.  Thus `/ w' pop's this limit, and others,
; as one would like it to.
(add-hook 'gnus-summary-prepared-hook 
          (lambda ()
            (if (or (string-match "^nnfolder:" gnus-newsgroup-name)
                    (string-match "^nnvirtual:Both" gnus-newsgroup-name)
                    (string-match "^nnml:" gnus-newsgroup-name))
                (jdc-gnus-summary-limit-exclude-unwanted))))

(defun jdc-gnus-summary-limit-exclude-unwanted ()
  (interactive)
  (gnus-summary-limit-to-marks "EG" t))

I also add the following to my summary-mode-hook:

(define-key gnus-summary-mode-map "/e" 'jdc-gnus-summary-limit-exclude-unwanted)

Then `/ w' shows me the expired articles when I choose to see them,
and `/ e' gets rid of them.

The only problem with this set-up is that entering a group is quite
slow, since the summary buffer gets generated twice, and the first
time tends to be a fair bit larger than the second time.  So it is
usually more than a factor of two slower than necessary.

What I would like is a variable "gnus-summary-show-expirable".  If
this is nil, then expirable articles aren't included by default,
but can be brought in with a new command.  I would suspect that
many users would like this behaviour.

Any thoughts?

-- 
Dan Christensen
jdc+news@uwo.ca