Re: request feedback on new function gnus-dired-attach

[Benjamin Rutt <rutt+news@cis.ohio-state.edu>]

NOTE: my outgoing mail has apparently been arriving on this mailing
list out-of-order lately, hopefully that won't cause any confusion for
anyone.

ShengHuo ZHU <zsh@cs.rochester.edu> writes:

> It is better to add a separate file, say gnus-dired.el, for gnus-dired
> minor mode. 

Here is my effort in this direction.  Feedback appreciated.  A few
things I'm not sure about:

1) did I define the `gnus-dired-mode-map' keymap correctly?  (I know
   you mentioned something about stealing a special (or customizable)
   prefix.  I just stuck C-c C-a in there.

2) I didn't think there should be a mode line string for this minor
   mode, so I left it empty.

Here begins the file gnus-dired.el:

;;; gnus-dired.el --- utility functions where dired and gnus meet

;; Copyright (C) 1996, 1997, 1998, 1999, 2001
;;        Free Software Foundation, Inc.

;; Author: Benjamin Rutt <brutt@bloomington.in.us>
;; Keywords: news, extensions

;; This file is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; This file is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to
;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; Provide utility functions for intersections of gnus and dired.

;;; Code:

(defvar gnus-dired-mode nil
  "Minor mode for intersections of gnus and dired.")

(defvar gnus-dired-mode-map nil)

(unless gnus-dired-mode-map
  (setq gnus-dired-mode-map (make-sparse-keymap))

  (gnus-define-keys gnus-dired-mode-map
    "\C-c\C-a" gnus-dired-attach))

(defun gnus-dired-mode (&optional arg)
  "Minor mode for intersections of gnus and dired.

\\{gnus-dired-mode-map}"
  (interactive "P")
  (when (eq major-mode 'dired-mode)
    (set (make-local-variable 'gnus-dired-mode)
	 (if (null arg) (not gnus-dired-mode)
	   (> (prefix-numeric-value arg) 0)))
    (when gnus-dired-mode
      (gnus-add-minor-mode 'gnus-dired-mode "" gnus-dired-mode-map)
      (gnus-run-hooks 'gnus-dired-mode-hook))))

;; Method to attach files to a gnus composition.
(defun gnus-dired-attach (files-to-attach)
  "Attach dired's marked files to a gnus message composition.
If called non-interactively, FILES-TO-ATTACH should be a list of
filenames."
  (interactive
   (list
    (delq nil
	  (mapcar
	   ;; don't attach directories
	   (lambda (f) (if (file-directory-p f) nil f))
	   (nreverse (dired-map-over-marks (dired-get-filename) nil))))))
  (let ((destination nil)
	(files-str nil)
	(bufs nil))
    ;; warn if user tries to attach without any files marked 
    (if (null files-to-attach)
	(message "No files marked to attach")
      (setq files-str
	    (mapconcat
	     (lambda (f) (file-name-nondirectory f))
	     files-to-attach ", "))
      (setq bufs (message-buffers))
    
      ;; set up destination message buffer
      (if (and bufs
	       (y-or-n-p "Attach files to existing message buffer? "))
	  (setq destination
		(if (= (length bufs) 1)
		    (get-buffer (car bufs))
		  (completing-read "Attach to which message buffer: "
				   (mapcar
				    (lambda (b)
				      (cons b (get-buffer b)))
				    bufs)
				   nil t)))
	;; setup a new gnus message buffer
	(gnus-setup-message 'message (message-mail))
	(setq destination (current-buffer)))

      ;; set buffer to destination buffer, and attach files
      (set-buffer destination)
      (goto-char (point-max))		;attach at end of buffer
      (while files-to-attach
	(mml-attach-file (car files-to-attach)
			 (or (mm-default-file-encoding (car files-to-attach))
			     "application/octet-stream") nil)
	(setq files-to-attach (cdr files-to-attach)))
      (message "Attached file(s) %s" files-str))))

(provide 'gnus-dired)
;;; gnus-dired.el ends here

-- 
Benjamin