Piping an article, imap numbering

[Alexander Kotelnikov <sacha@myxomop.com>]

Hello.

I have a mailbox for mail which was not splitted anywhere and probably
(and almost always) is spam. So once a certain period I want all this
mail to be piped to "sa-learn --spam", marked as read and moved to a
spam mailbox (I do not delete them in case of mistake). I wrote a
function that helps me but I believe it is not completely elegant:

(defun my-gnus-sa-learn-and-move(&optional n)
  ""
  (interactive "p")
  (mapc
   (lambda (n)
     (gnus-summary-goto-article n)
     (gnus-summary-show-article t)
     (gnus-summary-save-in-pipe "sa-learn --spam")
     (gnus-summary-move-article 1 "nnimap+myxomop:INBOX.spam")
     )
   (gnus-summary-work-articles n)
   )
  (delete-other-windows)
)
(add-hook 'gnus-summary-mode-hook
          '(lambda ()
             (define-key gnus-summary-mode-map "\C-cs"
               'my-gnus-sa-learn-and-move)))

What I do not like here:
1. I found 4 functions for piping messages:
   gnus-summary-save-in-pipe, (defined in gnus-art.el!)
   gnus-summary-pipe-output,
   gnus-summary-pipe-message,
   message-pipe-buffer-body
isn't it too much and too redundant?
2. None ot these functions accepts article number as an argument, so
one need to open an article first and then process it.

The other question is if I have an imap mailbox with several messages,
read them and delete, say, the last one, then after one more is
received *Group* shows '2' for corresponding group (and it is clear
why), but can I ask gnus to be more intelligent here?
--
Alexander Kotelnikov
Saint-Petersburg, Russia