* mu4e: support extracting ranges of attachments (C-u e); contributed by

Stephen Eglen.

emacs/mu4e-utils.el

@@ -726,6 +726,42 @@ mu4e logs some of its internal workings to a log-buffer. See
     (unless (buffer-live-p buf)
       (error "No debug log available"))
     (switch-to-buffer buf)))
+
+
+
+(defun mu4e-split-ranges-to-numbers (str n)
+  "Convert STR containing attachment numbers into a list of numbers.
+STR is a string; N is the highest possible number in the list.
+This includes expanding e.g. 3-5 into 3,4,5.  If the letter
+\"a\" ('all')) is given, that is expanded to a list with numbers [1..n]."
+  (let ((str-split (split-string str))
+	 beg end list)
+    (dolist (elem str-split list)
+      ;; special number "a" converts into all attachments 1-N.
+      (when (equal elem "a")
+	(setq elem (concat "1-" (int-to-string n))))
+      (if (string-match "\\([0-9]+\\)-\\([0-9]+\\)" elem)
+	;; we have found a range A-B, which needs converting
+	;; into the numbers A, A+1, A+2, ... B.
+	(progn
+	  (setq beg (string-to-int (match-string 1 elem))
+	    end (string-to-int (match-string 2 elem)))
+	  (while (<= beg end)
+	    (add-to-list 'list beg 'append)
+	    (setq beg (1+ beg))))
+	;; else just a number
+	(add-to-list 'list (string-to-int elem) 'append)))
+    ;; Check that all numbers are valid.
+    (mapc
+      '(lambda (x)
+	 (cond
+	   ((> x n)
+	     (error "Attachment %d bigger than maximum (%d)" x n))
+	   ((< x 1)
+	     (error "Attachment number must be greater than 0 (%d)" x))))
+      list)))
+
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (defvar mu4e-imagemagick-identify "identify"

emacs/mu4e-view.el

@@ -753,16 +753,23 @@ all messages in the thread at point in the headers view."
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; attachment handling
-(defun mu4e~view-get-attach-num (prompt msg)
+(defun mu4e~view-get-attach-num (prompt msg &optional multi)
   "Ask the user with PROMPT for an attachment number for MSG, and
   ensure it is valid. The number is [1..n] for attachments
-  [0..(n-1)] in the message."
-  (let* ((count (hash-table-count mu4e~view-attach-map)))
+  [0..(n-1)] in the message. If MULTI is nil, return the number for
+  the attachment; otherwise (MULTI is non-nil), accept ranges of
+  attachment numbers, as per `mu4e-split-ranges-to-numbers', and
+  return the corresponding string."
+  (let* ((count (hash-table-count mu4e~view-attach-map)) (def))
     (when (zerop count) (error "No attachments for this message"))
-    (if (= count 1)
-      (read-number (mu4e-format "%s: " prompt) 1)
-      (read-number (mu4e-format "%s (1-%d): " prompt count)))))
-
+    (if (not multi)
+      (if (= count 1)
+	(read-number (mu4e-format "%s: " prompt) 1)
+	(read-number (mu4e-format "%s (1-%d): " prompt count)))
+      (progn
+	(setq def (if (= count 1) "1" (format "1-%d" count)))
+	(read-string (mu4e-format "%s (default %s): " prompt def) nil nil def)))))
+ 
 (defun mu4e~view-get-attach (msg attnum)
   "Return the attachment plist in MSG corresponding to attachment
 number ATTNUM."
@@ -773,7 +780,7 @@ number ATTNUM."
       (plist-get msg :parts))))
 
 
-(defun mu4e-view-save-attachment (&optional msg attnum)
+(defun mu4e-view-save-attachment-single (&optional msg attnum)
   "Save attachment number ATTNUM (or ask if nil) from MSG (or
 message-at-point if nil) to disk."
   (interactive)
@@ -795,6 +802,31 @@ message-at-point if nil) to disk."
     (mu4e~proc-extract
       'save (plist-get msg :docid) index path)))
 
+(defun mu4e-view-save-attachment-multi (&optional msg)
+  "Offer to save multiple email attachments from the current message.
+Default is to save all messages, [1..n], where n is the number of
+attachments.  You can type multiple values separated by space, e.g.
+  1 3-6 8
+will save attachments 1,3,4,5,6 and 8.
+
+Furthermore, there is a shortcut \"a\" which so means all
+attachments, but as this is the default, you may not need it."
+  (interactive)
+  (let* ((msg (or msg (mu4e-message-at-point)))
+	 (attachstr (mu4e~view-get-attach-num
+		      "Attachment number range (or 'a' for 'all')" msg t))
+	 (attachnums (mu4e-split-ranges-to-numbers attachstr count)))
+    (dolist (num attachnums)
+      (mu4e-view-save-attachment-single msg num))))
+
+(defun mu4e-view-save-attachment (&optional multi)
+  "Offer to save attachment(s). If MULTI (prefix-argument) is nil,
+save a single one, otherwise, offer to save a range of
+attachments."
+  (interactive "P")
+  (if multi
+    (mu4e-view-save-attachment-multi)
+    (mu4e-view-save-attachment-single)))
 
 (defun mu4e-view-open-attachment (&optional msg attnum)
   "Open attachment number ATTNUM (or ask if nil) from MSG (or

emacs/mu4e.texi

@@ -734,6 +734,7 @@ g            go to (visit) numbered URL (using `browse-url')
              (or: <mouse-2> or RET with point on url)
 e            extract (save) attachment (asks for number)
              (or: <mouse-2> or RET with point on attachment)
+             C-u e will extract multiple attachments
 o            open attachment (asks for number)
              (or: <S-mouse-2> or S-RET with point on attachment)
 A            execute some action on an attachment
@@ -761,6 +762,11 @@ variable @code{mu4e-attachment-dir}, for example:
 (setq mu4e-attachment-dir (file-name-expand "~/Downloads"))
 @end lisp
 
+If you want to extract multiple attachments at once, you can do so by
+prefixing the extracting command by @key{C-u}; so @key{C-u e} will ask you for
+a range of attachments to extract (for example, 1 3-6 8). Range @t{a} is a
+shortcut for @emph{all} attachments. 
+
 @subsection Viewing images inline
 @anchor{Viewing images inline}