* lisp/gnus: Quote functions with #'

To get better warnings, try and use #' to quote function names.

* lisp/gnus/canlock.el:
* lisp/gnus/deuglify.el:
* lisp/gnus/gmm-utils.el:
* lisp/gnus/gnus-agent.el:
* lisp/gnus/gnus-art.el:
* lisp/gnus/gnus-bookmark.el:
* lisp/gnus/gnus-cache.el:
* lisp/gnus/gnus-cite.el:
* lisp/gnus/gnus-cus.el:
* lisp/gnus/gnus-delay.el:
* lisp/gnus/gnus-diary.el:
* lisp/gnus/gnus-dired.el:
* lisp/gnus/gnus-draft.el:
* lisp/gnus/gnus-fun.el:
* lisp/gnus/gnus-group.el:
* lisp/gnus/gnus-html.el:
* lisp/gnus/gnus-int.el:
* lisp/gnus/gnus-kill.el:
* lisp/gnus/gnus-mlspl.el:
* lisp/gnus/gnus-msg.el:
* lisp/gnus/gnus-notifications.el:
* lisp/gnus/gnus-picon.el:
* lisp/gnus/gnus-registry.el:
* lisp/gnus/gnus-rfc1843.el:
* lisp/gnus/gnus-salt.el:
* lisp/gnus/gnus-score.el:
* lisp/gnus/gnus-search.el:
* lisp/gnus/gnus-sieve.el:
* lisp/gnus/gnus-srvr.el:
* lisp/gnus/gnus-start.el:
* lisp/gnus/gnus-topic.el:
* lisp/gnus/gnus-undo.el:
* lisp/gnus/gnus-util.el:
* lisp/gnus/gnus-uu.el:
* lisp/gnus/gnus.el:
* lisp/gnus/mail-source.el:
* lisp/gnus/message.el:
* lisp/gnus/mm-archive.el:
* lisp/gnus/mm-decode.el:
* lisp/gnus/mm-url.el:
* lisp/gnus/mm-util.el:
* lisp/gnus/mm-view.el:
* lisp/gnus/mml-sec.el:
* lisp/gnus/mml-smime.el:
* lisp/gnus/mml.el:
* lisp/gnus/nnagent.el:
* lisp/gnus/nndiary.el:
* lisp/gnus/nndoc.el:
* lisp/gnus/nndraft.el:
* lisp/gnus/nnfolder.el:
* lisp/gnus/nnheader.el:
* lisp/gnus/nnmail.el:
* lisp/gnus/nnmaildir.el:
* lisp/gnus/nnmairix.el:
* lisp/gnus/nnmh.el:
* lisp/gnus/nnml.el:
* lisp/gnus/nnrss.el:
* lisp/gnus/nnselect.el:
* lisp/gnus/nnspool.el:
* lisp/gnus/nnvirtual.el:
* lisp/gnus/nnweb.el:
* lisp/gnus/smiley.el:
* lisp/gnus/smime.el:
* lisp/gnus/spam-report.el:
* lisp/gnus/spam-stat.el:
* lisp/gnus/spam-wash.el:
* lisp/gnus/spam.el:

67 files changed, 512 insertions, 497 deletions

diff --git a/lisp/gnus/canlock.el b/lisp/gnus/canlock.el
index 6c8c1a5927a..e203ebc0a99 100644
--- a/lisp/gnus/canlock.el
+++ b/lisp/gnus/canlock.el
@@ -30,7 +30,7 @@
 ;; Key) header in a news article by using a hook which will be evaluated
 ;; just before sending an article as follows:
 ;;
-;; (add-hook '*e**a*e-header-hook 'canlock-insert-header t)
+;; (add-hook '*e**a*e-header-hook #'canlock-insert-header t)
 ;;
 ;; Verifying Cancel-Lock is mainly a function of news servers, however,
 ;; you can verify your own article using the command `canlock-verify' in
diff --git a/lisp/gnus/deuglify.el b/lisp/gnus/deuglify.el
index b77dcdd4624..4f9ac26ed84 100644
--- a/lisp/gnus/deuglify.el
+++ b/lisp/gnus/deuglify.el
@@ -155,15 +155,15 @@
 ;; To automatically invoke deuglification on every article you read,
 ;; put something like that in your .gnus:
 ;;
-;; (add-hook 'gnus-article-decode-hook 'gnus-article-outlook-unwrap-lines)
+;; (add-hook 'gnus-article-decode-hook #'gnus-article-outlook-unwrap-lines)
 ;;
 ;; or _one_ of the following lines:
 ;;
 ;; ;; repair broken attribution lines
-;; (add-hook 'gnus-article-decode-hook 'gnus-article-outlook-repair-attribution)
+;; (add-hook 'gnus-article-decode-hook #'gnus-article-outlook-repair-attribution)
 ;;
 ;; ;; repair broken attribution lines and citations
-;; (add-hook 'gnus-article-decode-hook 'gnus-article-outlook-rearrange-citation)
+;; (add-hook 'gnus-article-decode-hook #'gnus-article-outlook-rearrange-citation)
 ;;
 ;; Note that there always may be some false positives, so I suggest
 ;; using the manual invocation.  After deuglification you may want to
diff --git a/lisp/gnus/gmm-utils.el b/lisp/gnus/gmm-utils.el
index ab97c593d9c..5e27a2f93a2 100644
--- a/lisp/gnus/gmm-utils.el
+++ b/lisp/gnus/gmm-utils.el
@@ -69,18 +69,18 @@ Guideline for numbers:
 7 - not very important messages on stuff
 9 - messages inside loops."
   (if (<= level gmm-verbose)
-      (apply 'message args)
+      (apply #'message args)
     ;; We have to do this format thingy here even if the result isn't
     ;; shown - the return value has to be the same as the return value
     ;; from `message'.
-    (apply 'format args)))
+    (apply #'format args)))
 
 ;;;###autoload
 (defun gmm-error (level &rest args)
   "Beep an error if LEVEL is equal to or less than `gmm-verbose'.
 ARGS are passed to `message'."
   (when (<= (floor level) gmm-verbose)
-    (apply 'message args)
+    (apply #'message args)
     (ding)
     (let (duration)
       (when (and (floatp level)
@@ -215,18 +215,18 @@ DEFAULT-MAP specifies the default key map for ICON-LIST."
                      ;; The dummy `gmm-ignore', see `gmm-tool-bar-item'
                      ;; widget.  Suppress tooltip by adding `:enable nil'.
                      (if (fboundp 'tool-bar-local-item)
-                         (apply 'tool-bar-local-item icon nil nil
+                         (apply #'tool-bar-local-item icon nil nil
                                 map :enable nil props)
                        ;; (tool-bar-local-item ICON DEF KEY MAP &rest PROPS)
                        ;; (tool-bar-add-item ICON DEF KEY &rest PROPS)
-                       (apply 'tool-bar-add-item icon nil nil :enable nil props)))
+                       (apply #'tool-bar-add-item icon nil nil :enable nil props)))
                     ((equal fmap t) ;; Not a menu command
-                     (apply 'tool-bar-local-item
+                     (apply #'tool-bar-local-item
                             icon command
                             (intern icon) ;; reuse icon or fmap here?
                             map props))
                     (t ;; A menu command
-                     (apply 'tool-bar-local-item-from-menu
+                     (apply #'tool-bar-local-item-from-menu
                             ;; (apply 'tool-bar-local-item icon def key
                             ;; tool-bar-map props)
                             command icon map (symbol-value fmap)
diff --git a/lisp/gnus/gnus-agent.el b/lisp/gnus/gnus-agent.el
index 46a4af8214a..cb679b849f5 100644
--- a/lisp/gnus/gnus-agent.el
+++ b/lisp/gnus/gnus-agent.el
@@ -248,9 +248,9 @@ Actually a hash table holding subjects mapped to t.")
   (gnus-agent-read-servers)
   (gnus-category-read)
   (gnus-agent-create-buffer)
-  (add-hook 'gnus-group-mode-hook 'gnus-agent-mode)
-  (add-hook 'gnus-summary-mode-hook 'gnus-agent-mode)
-  (add-hook 'gnus-server-mode-hook 'gnus-agent-mode))
+  (add-hook 'gnus-group-mode-hook #'gnus-agent-mode)
+  (add-hook 'gnus-summary-mode-hook #'gnus-agent-mode)
+  (add-hook 'gnus-server-mode-hook #'gnus-agent-mode))
 
 (defun gnus-agent-create-buffer ()
   (if (gnus-buffer-live-p gnus-agent-overview-buffer)
@@ -701,7 +701,7 @@ be a select method."
     (message-narrow-to-headers)
     (let* ((gcc (mail-fetch-field "gcc" nil t))
            (methods (and gcc
-                         (mapcar 'gnus-inews-group-method
+                         (mapcar #'gnus-inews-group-method
                                  (message-unquote-tokens
                                   (message-tokenize-header
                                    gcc " ,")))))
@@ -1057,7 +1057,8 @@ article's mark is toggled."
       (let* ((alist (gnus-agent-load-alist gnus-newsgroup-name))
              (headers (sort (mapcar (lambda (h)
                                       (mail-header-number h))
-                                    gnus-newsgroup-headers) '<))
+                                    gnus-newsgroup-headers)
+                            #'<))
              (cached (and gnus-use-cache gnus-newsgroup-cached))
              (undownloaded (list nil))
              (tail-undownloaded undownloaded)
@@ -1128,7 +1129,7 @@ downloadable."
   (when gnus-newsgroup-processable
     (setq gnus-newsgroup-downloadable
           (let* ((dl gnus-newsgroup-downloadable)
-                 (processable (sort (copy-tree gnus-newsgroup-processable) '<))
+                 (processable (sort (copy-tree gnus-newsgroup-processable) #'<))
                  (gnus-newsgroup-downloadable processable))
             (gnus-agent-summary-fetch-group)
 
@@ -1820,7 +1821,7 @@ article numbers will be returned."
       (dolist (arts (gnus-info-marks (gnus-get-info group)))
         (unless (memq (car arts) '(seen recent killed cache))
           (setq articles (gnus-range-add articles (cdr arts)))))
-      (setq articles (sort (gnus-uncompress-sequence articles) '<)))
+      (setq articles (sort (gnus-uncompress-sequence articles) #'<)))
 
     ;; At this point, I have the list of articles to consider for
     ;; fetching.  This is the list that I'll return to my caller. Some
@@ -2066,7 +2067,7 @@ doesn't exist, to valid the overview buffer."
                         alist (cdr alist))
                   (while sequence
                     (push (cons (pop sequence) state) uncomp)))
-                (setq alist (sort uncomp 'car-less-than-car)))
+                (setq alist (sort uncomp #'car-less-than-car)))
               (setq changed-version (not (= 2 gnus-agent-article-alist-save-format)))))
             (when changed-version
               (let ((gnus-agent-article-alist alist))
@@ -2408,13 +2409,13 @@ modified) original contents, they are first saved to their own file."
                 (setq marked-articles (nconc (gnus-uncompress-range arts)
                                              marked-articles))
                 ))))
-        (setq marked-articles (sort marked-articles '<))
+        (setq marked-articles (sort marked-articles #'<))
 
         ;; Fetch any new articles from the server
         (setq articles (gnus-agent-fetch-headers group))
 
         ;; Merge new articles with marked
-        (setq articles (sort (append marked-articles articles) '<))
+        (setq articles (sort (append marked-articles articles) #'<))
 
         (when articles
           ;; Parse them and see which articles we want to fetch.
@@ -3127,7 +3128,7 @@ FORCE is equivalent to setting the expiration predicates to true."
                        (gnus-uncompress-range
                         (cons (caar alist)
                               (caar (last alist))))
-                       (sort articles '<)))))
+                       (sort articles #'<)))))
               (marked ;; More articles that are excluded from the
                ;; expiration process
                (cond (gnus-agent-expire-all
@@ -3859,7 +3860,7 @@ If REREAD is not nil, downloaded articles are marked as unread."
                                                           (string-to-number name)))
                                                    (directory-files
                                                     dir nil "\\`[0-9]+\\'" t)))
-                                 '>)
+                                 #'>)
                          (progn (gnus-make-directory dir) nil)))
            nov-arts
            alist header
@@ -4163,7 +4164,7 @@ modified."
            (path (gnus-agent-group-pathname group))
            (entry (gethash path gnus-agent-total-fetched-hashtb)))
       (if entry
-          (apply '+ entry)
+          (apply #'+ entry)
         (let ((gnus-agent-inhibit-update-total-fetched-for (not no-inhibit)))
           (+
            (gnus-agent-update-view-total-fetched-for  group nil method path)
diff --git a/lisp/gnus/gnus-art.el b/lisp/gnus/gnus-art.el
index 6a66dc65421..ca24e6f251f 100644
--- a/lisp/gnus/gnus-art.el
+++ b/lisp/gnus/gnus-art.el
@@ -1623,7 +1623,7 @@ It is a string, such as \"PGP\".  If nil, ask user."
   :group 'gnus-article
   :type 'boolean)
 
-(defcustom gnus-blocked-images 'gnus-block-private-groups
+(defcustom gnus-blocked-images #'gnus-block-private-groups
   "Images that have URLs matching this regexp will be blocked.
 Note that the main reason external images are included in HTML
 emails (these days) is to allow tracking whether you've read the
@@ -2987,7 +2987,7 @@ message header will be added to the bodies of the \"text/html\" parts."
              (when tmp-file
                (add-to-list 'gnus-article-browse-html-temp-list tmp-file))
              (add-hook 'gnus-summary-prepare-exit-hook
-                       'gnus-article-browse-delete-temp-files)
+                       #'gnus-article-browse-delete-temp-files)
              (add-hook 'gnus-exit-gnus-hook
                        (lambda  ()
                          (gnus-article-browse-delete-temp-files t)))
diff --git a/lisp/gnus/gnus-bookmark.el b/lisp/gnus/gnus-bookmark.el
index 57859d806c9..d1af64d6d66 100644
--- a/lisp/gnus/gnus-bookmark.el
+++ b/lisp/gnus/gnus-bookmark.el
@@ -279,7 +279,7 @@ So the cdr of each bookmark is an alist too.")
   (gnus-bookmark-maybe-load-default-file)
   (let* ((bookmark (or bmk-name
                        (gnus-completing-read "Jump to bookmarked article"
-                                             (mapcar 'car gnus-bookmark-alist))))
+                                             (mapcar #'car gnus-bookmark-alist))))
          (bmk-record (cadr (assoc bookmark gnus-bookmark-alist)))
          (group (cdr (assoc 'group bmk-record)))
          (message-id (cdr (assoc 'message-id bmk-record))))
diff --git a/lisp/gnus/gnus-cache.el b/lisp/gnus/gnus-cache.el
index 36657e46219..bea3d3bf03f 100644
--- a/lisp/gnus/gnus-cache.el
+++ b/lisp/gnus/gnus-cache.el
@@ -518,7 +518,7 @@ Returns the list of articles removed."
       (setq articles
             (sort (mapcar (lambda (name) (string-to-number name))
                           (directory-files dir nil "\\`[0-9]+\\'" t))
-                  '<))
+                  #'<))
       ;; Update the cache active file, just to synch more.
       (if articles
           (progn
@@ -714,7 +714,7 @@ If LOW, update the lower bound instead."
           (push (string-to-number (file-name-nondirectory (pop files))) nums)
         (push (pop files) alphs)))
     ;; If we have nums, then this is probably a valid group.
-    (when (setq nums (sort nums '<))
+    (when (setq nums (sort nums #'<))
       (puthash group
                (cons (car nums) (car (last nums)))
                gnus-cache-active-hashtb))
@@ -884,7 +884,7 @@ supported."
       (setq gnus-cache-total-fetched-hashtb (gnus-make-hashtable 1000)))
     (let* ((entry (gethash group gnus-cache-total-fetched-hashtb)))
       (if entry
-          (apply '+ entry)
+          (apply #'+ entry)
         (let ((gnus-cache-inhibit-update-total-fetched-for (not no-inhibit)))
           (+
            (gnus-cache-update-overview-total-fetched-for group nil)
diff --git a/lisp/gnus/gnus-cite.el b/lisp/gnus/gnus-cite.el
index d02e898e230..a6d1101e015 100644
--- a/lisp/gnus/gnus-cite.el
+++ b/lisp/gnus/gnus-cite.el
@@ -445,7 +445,7 @@ Lines matching `gnus-cite-attribution-suffix' and perhaps
       (gnus-article-search-signature)
       (push (cons (point-marker) "") marks)
       ;; Sort the marks.
-      (setq marks (sort marks 'car-less-than-car))
+      (setq marks (sort marks #'car-less-than-car))
       (let ((omarks marks))
         (setq marks nil)
         (while (cdr omarks)
@@ -999,7 +999,7 @@ See also the documentation for `gnus-article-highlight-citation'."
                 cites (cdr cites)
                 candidate (car cite)
                 numbers (cdr cite)
-                first (apply 'min numbers)
+                first (apply #'min numbers)
                 compare (if size (length candidate) first))
           (and (> first limit)
                regexp
@@ -1125,7 +1125,7 @@ See also the documentation for `gnus-article-highlight-citation'."
   "Search for a cited line and set match data accordingly.
 Returns nil if there is no such line before LIMIT, t otherwise."
   (when (re-search-forward gnus-message-cite-prefix-regexp limit t)
-    (let ((cdepth (min (length (apply 'concat
+    (let ((cdepth (min (length (apply #'concat
                                       (split-string
                                        (match-string-no-properties 0)
                                        "[\t [:alnum:]]+")))
diff --git a/lisp/gnus/gnus-cus.el b/lisp/gnus/gnus-cus.el
index dc14943a060..a36ef0cbec8 100644
--- a/lisp/gnus/gnus-cus.el
+++ b/lisp/gnus/gnus-cus.el
@@ -417,7 +417,7 @@ category."))
           (setq tmp (cdr tmp))))
 
       (setq gnus-custom-params
-            (apply 'widget-create 'group
+            (apply #'widget-create 'group
                    :value values
                    (delq nil
                          (list `(set :inline t
diff --git a/lisp/gnus/gnus-delay.el b/lisp/gnus/gnus-delay.el
index 477ad88a9ca..74147f2092f 100644
--- a/lisp/gnus/gnus-delay.el
+++ b/lisp/gnus/gnus-delay.el
@@ -179,7 +179,7 @@ This tells Gnus to look for delayed messages after getting new news.
 The optional arg NO-KEYMAP is ignored.
 Checking delayed messages is skipped if optional arg NO-CHECK is non-nil."
   (unless no-check
-    (add-hook 'gnus-get-new-news-hook 'gnus-delay-send-queue)))
+    (add-hook 'gnus-get-new-news-hook #'gnus-delay-send-queue)))
 
 (provide 'gnus-delay)
 
diff --git a/lisp/gnus/gnus-diary.el b/lisp/gnus/gnus-diary.el
index 78f1e53ff7a..561a15b8092 100644
--- a/lisp/gnus/gnus-diary.el
+++ b/lisp/gnus/gnus-diary.el
@@ -276,13 +276,13 @@ Optional prefix (or REVERSE argument) means sort in reverse order."
     (gnus-diary-update-group-parameters group)))
 
 (add-hook 'nndiary-request-create-group-functions
-          'gnus-diary-update-group-parameters)
+          #'gnus-diary-update-group-parameters)
 ;; Now that we have `gnus-subscribe-newsgroup-functions', this is not needed
 ;; anymore. Maybe I should remove this completely.
 (add-hook 'nndiary-request-update-info-functions
-          'gnus-diary-update-group-parameters)
+          #'gnus-diary-update-group-parameters)
 (add-hook 'gnus-subscribe-newsgroup-functions
-          'gnus-diary-maybe-update-group-parameters)
+          #'gnus-diary-maybe-update-group-parameters)
 
 
 ;; Diary Message Checking ===================================================
@@ -360,7 +360,7 @@ If ARG (or prefix) is non-nil, force prompting for all fields."
                                  header ": ")))
              (setq value
                    (if (listp (nth 1 head))
-                       (gnus-completing-read prompt (cons "*" (mapcar 'car (nth 1 head)))
+                       (gnus-completing-read prompt (cons "*" (mapcar #'car (nth 1 head)))
                                              t value
                                              'gnus-diary-header-value-history)
                      (read-string prompt value
diff --git a/lisp/gnus/gnus-dired.el b/lisp/gnus/gnus-dired.el
index 6f231c4fbb8..e78163afe28 100644
--- a/lisp/gnus/gnus-dired.el
+++ b/lisp/gnus/gnus-dired.el
@@ -29,7 +29,7 @@
 ;; following in your ~/.gnus:
 
 ;; (require 'gnus-dired) ;, isn't needed due to autoload cookies
-;; (add-hook 'dired-mode-hook 'turn-on-gnus-dired-mode)
+;; (add-hook 'dired-mode-hook #'turn-on-gnus-dired-mode)
 
 ;; Note that if you visit dired buffers before your ~/.gnus file has
 ;; been read, those dired buffers won't have the keybindings in
diff --git a/lisp/gnus/gnus-draft.el b/lisp/gnus/gnus-draft.el
index 5f7ed386297..3b380f30c66 100644
--- a/lisp/gnus/gnus-draft.el
+++ b/lisp/gnus/gnus-draft.el
@@ -65,7 +65,7 @@
     ;; Set up the menu.
     (when (gnus-visual-p 'draft-menu 'menu)
       (gnus-draft-make-menu-bar))
-    (add-hook 'gnus-summary-prepare-exit-hook 'gnus-draft-clear-marks t t))))
+    (add-hook 'gnus-summary-prepare-exit-hook #'gnus-draft-clear-marks t t))))
 
 ;;; Commands
 
diff --git a/lisp/gnus/gnus-fun.el b/lisp/gnus/gnus-fun.el
index 615f4a55bc5..8ce6990804d 100644
--- a/lisp/gnus/gnus-fun.el
+++ b/lisp/gnus/gnus-fun.el
@@ -268,9 +268,9 @@ colors of the displayed X-Faces."
            'xface
            (gnus-put-image
             (if (gnus-image-type-available-p 'xface)
-                (apply 'gnus-create-image (concat "X-Face: " data) 'xface t
+                (apply #'gnus-create-image (concat "X-Face: " data) 'xface t
                        (cdr (assq 'xface gnus-face-properties-alist)))
-              (apply 'gnus-create-image pbm 'pbm t
+              (apply #'gnus-create-image pbm 'pbm t
                      (cdr (assq 'pbm gnus-face-properties-alist))))
             nil 'xface))
           (gnus-add-wash-type 'xface))))))
@@ -325,7 +325,7 @@ colors of the displayed X-Faces."
   (dotimes (i 255)
     (push (format format i i i i i i)
           values))
-  (mapconcat 'identity values " ")))
+  (mapconcat #'identity values " ")))
 
 (defun gnus-funcall-no-warning (function &rest args)
   (when (fboundp function)
diff --git a/lisp/gnus/gnus-group.el b/lisp/gnus/gnus-group.el
index ff792c57065..a165752881a 100644
--- a/lisp/gnus/gnus-group.el
+++ b/lisp/gnus/gnus-group.el
@@ -1361,7 +1361,7 @@ if it is a string, only list groups matching REGEXP."
               (and (>= level gnus-level-zombie)
                    (<= lowest gnus-level-zombie)))
       (gnus-group-prepare-flat-list-dead
-       (setq gnus-zombie-list (sort gnus-zombie-list 'string<))
+       (setq gnus-zombie-list (sort gnus-zombie-list #'string<))
        gnus-level-zombie ?Z
        regexp))
     (when not-in-list
@@ -1372,7 +1372,7 @@ if it is a string, only list groups matching REGEXP."
       (gnus-group-prepare-flat-list-dead
        (cl-union
         not-in-list
-        (setq gnus-killed-list (sort gnus-killed-list 'string<))
+        (setq gnus-killed-list (sort gnus-killed-list #'string<))
         :test 'equal)
        gnus-level-killed ?K regexp))
 
@@ -1608,7 +1608,7 @@ Some value are bound so the form can use them."
              (cons 'unread (if (numberp (car entry)) (car entry) 0))
              (cons 'total (if active (1+ (- (cdr active) (car active))) 0))
              (cons 'mailp (apply
-                           'append
+                           #'append
                            (mapcar
                             (lambda (x)
                               (memq x (assoc
@@ -1883,7 +1883,7 @@ If FIRST-TOO, the current line is also eligible as a target."
   "Unmark all groups."
   (interactive)
   (save-excursion
-    (mapc 'gnus-group-remove-mark gnus-group-marked))
+    (mapc #'gnus-group-remove-mark gnus-group-marked))
   (gnus-group-position-point))
 
 (defun gnus-group-mark-region (unmark beg end)
@@ -2985,7 +2985,7 @@ and NEW-NAME will be prompted for."
   "Create one of the groups described in `gnus-useful-groups'."
   (interactive
    (let ((entry (assoc (gnus-completing-read "Create group"
-                                             (mapcar 'car gnus-useful-groups)
+                                             (mapcar #'car gnus-useful-groups)
                                              t)
                        gnus-useful-groups)))
      (list (cadr entry)
@@ -3118,7 +3118,7 @@ If there is, use Gnus to create an nnrss group"
                        (read-from-minibuffer "Title: "
                                              (gnus-newsgroup-savable-name
                                               (mapconcat
-                                               'identity
+                                               #'identity
                                                (split-string
                                                 (or (cdr (assoc 'title
                                                                 feedinfo))
@@ -3126,7 +3126,7 @@ If there is, use Gnus to create an nnrss group"
                                                " ")))))
                (desc  (read-from-minibuffer "Description: "
                                             (mapconcat
-                                             'identity
+                                             #'identity
                                              (split-string
                                               (or (cdr (assoc 'description
                                                               feedinfo))
@@ -4268,7 +4268,7 @@ If DONT-SCAN is non-nil, scan non-activated groups as well."
         (pop-to-buffer "*Gnus Help*")
         (buffer-disable-undo)
         (erase-buffer)
-        (setq groups (sort groups 'string<))
+        (setq groups (sort groups #'string<))
         (while groups
           ;; Groups may be entered twice into the list of groups.
           (when (not (string= (car groups) prev))
@@ -4494,7 +4494,7 @@ and the second element is the address."
   (interactive
    (list (let ((how (gnus-completing-read
                      "Which back end"
-                     (mapcar 'car (append gnus-valid-select-methods
+                     (mapcar #'car (append gnus-valid-select-methods
                                           gnus-server-alist))
                      t (cons "nntp" 0) 'gnus-method-history)))
            ;; We either got a back end name or a virtual server name.
@@ -4616,7 +4616,9 @@ and the second element is the address."
               (setcdr m (gnus-compress-sequence articles t)))
           (setcdr m (gnus-compress-sequence
                      (sort (nconc (gnus-uncompress-range (cdr m))
-                                  (copy-sequence articles)) '<) t))))))
+                                  (copy-sequence articles))
+                           #'<)
+                     t))))))
 
 (declare-function gnus-summary-add-mark "gnus-sum" (article type))
 
@@ -4684,7 +4686,7 @@ This command may read the active file."
                    ;; Cache active file might use "."
                    ;; instead of ":".
                    (gethash
-                    (mapconcat 'identity
+                    (mapconcat #'identity
                                (split-string group ":")
                                ".")
                     gnus-cache-active-hashtb))))
@@ -4808,7 +4810,7 @@ you the groups that have both dormant articles and cached articles."
                   (push n gnus-newsgroup-unselected))
                 (setq n (1+ n)))
               (setq gnus-newsgroup-unselected
-                    (sort gnus-newsgroup-unselected '<)))))
+                    (sort gnus-newsgroup-unselected #'<)))))
       (gnus-activate-group group)
       (gnus-group-make-articles-read group (list article))
       (when (and (gnus-group-auto-expirable-p group)
diff --git a/lisp/gnus/gnus-html.el b/lisp/gnus/gnus-html.el
index bb1ee5a806a..855d085c3a9 100644
--- a/lisp/gnus/gnus-html.el
+++ b/lisp/gnus/gnus-html.el
@@ -329,10 +329,10 @@ Use ALT-TEXT for the image string."
       (replace-match "" t t))
     (mm-url-decode-entities)))
 
-(defun gnus-html-insert-image (&rest args)
+(defun gnus-html-insert-image (&rest _args)
   "Fetch and insert the image under point."
   (interactive)
-  (apply 'gnus-html-display-image (get-text-property (point) 'gnus-image)))
+  (apply #'gnus-html-display-image (get-text-property (point) 'gnus-image)))
 
 (defun gnus-html-show-alt-text ()
   "Show the ALT text of the image under point."
diff --git a/lisp/gnus/gnus-int.el b/lisp/gnus/gnus-int.el
index 9c68773e19a..8bad44687b2 100644
--- a/lisp/gnus/gnus-int.el
+++ b/lisp/gnus/gnus-int.el
@@ -628,7 +628,7 @@ the group's summary.
           article-number)
       ;; Clean up the new summary and propagate the error
       (error (when group-is-new (gnus-summary-exit))
-             (apply 'signal err)))))
+             (apply #'signal err)))))
 
 (defun gnus-simplify-group-name (group)
   "Return the simplest representation of the name of GROUP.
diff --git a/lisp/gnus/gnus-kill.el b/lisp/gnus/gnus-kill.el
index 7e592026cd0..20ea9831052 100644
--- a/lisp/gnus/gnus-kill.el
+++ b/lisp/gnus/gnus-kill.el
@@ -641,7 +641,7 @@ Usage: emacs -batch -l ~/.emacs -l gnus -f gnus-batch-score"
   (let* ((gnus-newsrc-options-n
           (gnus-newsrc-parse-options
            (concat "options -n "
-                   (mapconcat 'identity command-line-args-left " "))))
+                   (mapconcat #'identity command-line-args-left " "))))
          (gnus-expert-user t)
          (mail-sources nil)
          (gnus-use-dribble-file nil)
diff --git a/lisp/gnus/gnus-mlspl.el b/lisp/gnus/gnus-mlspl.el
index ed8d15a2feb..77816d22eb0 100644
--- a/lisp/gnus/gnus-mlspl.el
+++ b/lisp/gnus/gnus-mlspl.el
@@ -196,13 +196,13 @@ Calling (gnus-group-split-fancy nil nil \"mail.others\") returns:
                         (concat
                          "\\("
                          (mapconcat
-                          'identity
+                          #'identity
                           (append
                            (and to-address (list (regexp-quote to-address)))
                            (and to-list (list (regexp-quote to-list)))
                            (and extra-aliases
                                 (if (listp extra-aliases)
-                                    (mapcar 'regexp-quote extra-aliases)
+                                    (mapcar #'regexp-quote extra-aliases)
                                   (list extra-aliases)))
                            (and split-regexp (list split-regexp)))
                           "\\|")
diff --git a/lisp/gnus/gnus-msg.el b/lisp/gnus/gnus-msg.el
index 836cc959c54..278b1d9d735 100644
--- a/lisp/gnus/gnus-msg.el
+++ b/lisp/gnus/gnus-msg.el
@@ -566,13 +566,18 @@ instead."
                          (symbol-value (car elem))))
             (throw 'found (cons (cadr elem) (caddr elem)))))))))
 
+(declare-function gnus-agent-possibly-do-gcc "gnus-agent" ())
+(declare-function gnus-cache-possibly-remove-article "gnus-cache"
+                  (article ticked dormant unread &optional force))
+
 (defun gnus-inews-add-send-actions (winconf buffer article
                                             &optional config yanked
                                             winconf-name)
-  (add-hook 'message-sent-hook (if gnus-agent 'gnus-agent-possibly-do-gcc
-                                 'gnus-inews-do-gcc) nil t)
+  (add-hook 'message-sent-hook (if gnus-agent #'gnus-agent-possibly-do-gcc
+                                 #'gnus-inews-do-gcc)
+            nil t)
   (when gnus-agent
-    (add-hook 'message-header-hook 'gnus-agent-possibly-save-gcc nil t))
+    (add-hook 'message-header-hook #'gnus-agent-possibly-save-gcc nil t))
   (setq message-post-method
         `(lambda (&optional arg)
            (gnus-post-method arg ,gnus-newsgroup-name)))
@@ -1038,8 +1043,8 @@ If SILENT, don't prompt the user."
                      gnus-post-method
                    (list gnus-post-method)))
                gnus-secondary-select-methods
-               (mapcar 'cdr gnus-server-alist)
-               (mapcar 'car gnus-opened-servers)
+               (mapcar #'cdr gnus-server-alist)
+               (mapcar #'car gnus-opened-servers)
                (list gnus-select-method)
                (list group-method)))
              method-alist post-methods method)
@@ -1067,7 +1072,7 @@ If SILENT, don't prompt the user."
                     ;; Just use the last value.
                     gnus-last-posting-server
                   (gnus-completing-read
-                   "Posting method" (mapcar 'car method-alist) t
+                   "Posting method" (mapcar #'car method-alist) t
                    (cons (or gnus-last-posting-server "") 0))))
           method-alist))))
      ;; Override normal method.
@@ -1341,13 +1346,13 @@ For the \"inline\" alternatives, also see the variable
                                                self))
                      "\n"))
             ((null self)
-             (insert "Gcc: " (mapconcat 'identity gcc ", ") "\n"))
+             (insert "Gcc: " (mapconcat #'identity gcc ", ") "\n"))
             ((eq self 'no-gcc-self)
              (when (setq gcc (delete
                               gnus-newsgroup-name
                               (delete (concat "\"" gnus-newsgroup-name "\"")
                                       gcc)))
-               (insert "Gcc: " (mapconcat 'identity gcc ", ") "\n")))))))
+               (insert "Gcc: " (mapconcat #'identity gcc ", ") "\n")))))))
 
 (defun gnus-summary-resend-message (address n &optional no-select)
   "Resend the current article to ADDRESS.
@@ -1387,7 +1392,7 @@ the message before resending."
           (setq user-mail-address tem))))
     ;; `gnus-summary-resend-message-insert-gcc' must run last.
     (add-hook 'message-header-setup-hook
-              'gnus-summary-resend-message-insert-gcc t)
+              #'gnus-summary-resend-message-insert-gcc t)
     (add-hook 'message-sent-hook
               `(lambda ()
                  (let ((rfc2047-encode-encoded-words nil))
@@ -1916,7 +1921,7 @@ this is a reply."
         (add-hook 'message-setup-hook
                   (cond
                    ((eq 'eval (car result))
-                    'ignore)
+                    #'ignore)
                    ((eq 'body (car result))
                     `(lambda ()
                        (save-excursion
@@ -1926,7 +1931,7 @@ this is a reply."
                     (setq-local message-signature nil)
                     (setq-local message-signature-file nil)
                     (if (not (cdr result))
-                        'ignore
+                        #'ignore
                       `(lambda ()
                          (save-excursion
                            (let ((message-signature ,(cdr result)))
diff --git a/lisp/gnus/gnus-notifications.el b/lisp/gnus/gnus-notifications.el
index e772dd8e625..39ef51b2b83 100644
--- a/lisp/gnus/gnus-notifications.el
+++ b/lisp/gnus/gnus-notifications.el
@@ -24,7 +24,7 @@
 
 ;; This implements notifications using `notifications-notify' on new
 ;; messages received.
-;; Use (add-hook 'gnus-after-getting-new-news-hook 'gnus-notifications)
+;; Use (add-hook 'gnus-after-getting-new-news-hook #'gnus-notifications)
 ;; to get notifications just after getting the new news.
 
 ;;; Code:
diff --git a/lisp/gnus/gnus-picon.el b/lisp/gnus/gnus-picon.el
index 92def9a72d0..a33316a5267 100644
--- a/lisp/gnus/gnus-picon.el
+++ b/lisp/gnus/gnus-picon.el
@@ -120,7 +120,7 @@ List of pairs (KEY . GLYPH) where KEY is either a filename or an URL.")
                 base (expand-file-name directory database))
           (while address
             (when (setq result (gnus-picon-find-image
-                                (concat base "/" (mapconcat 'downcase
+                                (concat base "/" (mapconcat #'downcase
                                                             (reverse address)
                                                             "/")
                                         "/" (downcase user) "/")))
@@ -158,7 +158,7 @@ replacement is added."
 
 (defun gnus-picon-create-glyph (file)
   (or (cdr (assoc file gnus-picon-glyph-alist))
-      (cdar (push (cons file (apply 'gnus-create-image
+      (cdar (push (cons file (apply #'gnus-create-image
                                     file nil nil
                                     gnus-picon-properties))
                   gnus-picon-glyph-alist))))
@@ -190,7 +190,7 @@ replacement is added."
                                 (gnus-picon-find-face
                                  (concat "unknown@"
                                          (mapconcat
-                                          'identity (cdr spec) "."))
+                                          #'identity (cdr spec) "."))
                                  gnus-picon-user-directories)))
              (setcar spec (cons (gnus-picon-create-glyph file)
                                 (car spec))))
@@ -201,7 +201,7 @@ replacement is added."
              (when (setq file (gnus-picon-find-face
                                (concat "unknown@"
                                        (mapconcat
-                                        'identity (nthcdr (1+ i) spec) "."))
+                                        #'identity (nthcdr (1+ i) spec) "."))
                                gnus-picon-domain-directories t))
                (setcar (nthcdr (1+ i) spec)
                        (cons (gnus-picon-create-glyph file)
@@ -214,10 +214,11 @@ replacement is added."
          (cl-case gnus-picon-style
                (right
                 (when (= (length addresses) 1)
-                  (setq len (apply '+ (mapcar (lambda (x)
-                                                (condition-case nil
-                                                    (car (image-size (car x)))
-                                                  (error 0))) spec)))
+                  (setq len (apply #'+ (mapcar (lambda (x)
+                                                 (condition-case nil
+                                                     (car (image-size (car x)))
+                                                   (error 0)))
+                                               spec)))
                   (when (> len 0)
                     (goto-char (point-at-eol))
                     (insert (propertize
@@ -256,7 +257,7 @@ replacement is added."
            (when (setq file (gnus-picon-find-face
                              (concat "unknown@"
                                      (mapconcat
-                                      'identity (nthcdr i spec) "."))
+                                      #'identity (nthcdr i spec) "."))
                              gnus-picon-news-directories t))
              (setcar (nthcdr i spec)
                      (cons (gnus-picon-create-glyph file)
diff --git a/lisp/gnus/gnus-registry.el b/lisp/gnus/gnus-registry.el
index 068066e38c9..7fdf6683138 100644
--- a/lisp/gnus/gnus-registry.el
+++ b/lisp/gnus/gnus-registry.el
@@ -891,7 +891,7 @@ Addresses without a name will say \"noname\"."
 
 (defun gnus-registry-sort-addresses (&rest addresses)
   "Return a normalized and sorted list of ADDRESSES."
-  (sort (mapcan #'gnus-registry-extract-addresses addresses) 'string-lessp))
+  (sort (mapcan #'gnus-registry-extract-addresses addresses) #'string-lessp))
 
 (defun gnus-registry-simplify-subject (subject)
   (if (stringp subject)
diff --git a/lisp/gnus/gnus-rfc1843.el b/lisp/gnus/gnus-rfc1843.el
index 107e96350bb..dca55af4605 100644
--- a/lisp/gnus/gnus-rfc1843.el
+++ b/lisp/gnus/gnus-rfc1843.el
@@ -56,11 +56,11 @@
 
 (defun rfc1843-gnus-setup ()
   "Setup HZ decoding for Gnus."
-  (add-hook 'gnus-article-decode-hook 'rfc1843-decode-article-body t)
+  (add-hook 'gnus-article-decode-hook #'rfc1843-decode-article-body t)
   (setq gnus-decode-encoded-word-function
-        'gnus-multi-decode-encoded-word-string
+        #'gnus-multi-decode-encoded-word-string
         gnus-decode-header-function
-        'gnus-multi-decode-header
+        #'gnus-multi-decode-header
         gnus-decode-encoded-word-methods
         (nconc gnus-decode-encoded-word-methods
                (list
diff --git a/lisp/gnus/gnus-salt.el b/lisp/gnus/gnus-salt.el
index abaa844f58a..d07d36e5441 100644
--- a/lisp/gnus/gnus-salt.el
+++ b/lisp/gnus/gnus-salt.el
@@ -103,7 +103,7 @@ It accepts the same format specs that `gnus-summary-line-format' does."
    ((not (derived-mode-p 'gnus-summary-mode)) (setq gnus-pick-mode nil))
    ((not gnus-pick-mode)
     ;; FIXME: a buffer-local minor mode removing globally from a hook??
-    (remove-hook 'gnus-message-setup-hook 'gnus-pick-setup-message))
+    (remove-hook 'gnus-message-setup-hook #'gnus-pick-setup-message))
    (t
     ;; Make sure that we don't select any articles upon group entry.
     (setq-local gnus-auto-select-first nil)
@@ -113,7 +113,7 @@ It accepts the same format specs that `gnus-summary-line-format' does."
     (gnus-update-format-specifications nil 'summary)
     (gnus-update-summary-mark-positions)
     ;; FIXME: a buffer-local minor mode adding globally to a hook??
-    (add-hook 'gnus-message-setup-hook 'gnus-pick-setup-message)
+    (add-hook 'gnus-message-setup-hook #'gnus-pick-setup-message)
     (setq-local gnus-summary-goto-unread 'never)
     ;; Set up the menu.
     (when (gnus-visual-p 'pick-menu 'menu)
diff --git a/lisp/gnus/gnus-score.el b/lisp/gnus/gnus-score.el
index e74c4980879..c6e08cee73a 100644
--- a/lisp/gnus/gnus-score.el
+++ b/lisp/gnus/gnus-score.el
@@ -683,7 +683,7 @@ current score file."
           (and gnus-extra-headers
                (equal (nth 1 entry) "extra")
                (intern                  ; need symbol
-                (let ((collection (mapcar 'symbol-name gnus-extra-headers)))
+                (let ((collection (mapcar #'symbol-name gnus-extra-headers)))
                   (gnus-completing-read
                    "Score extra header"  ; prompt
                    collection            ; completion list
@@ -932,7 +932,7 @@ SCORE is the score to add.
 EXTRA is the possible non-standard header."
   (interactive (list (gnus-completing-read "Header"
                                            (mapcar
-                                            'car
+                                            #'car
                                             (seq-filter
                                              (lambda (x) (fboundp (nth 2 x)))
                                              gnus-header-index))
@@ -1258,8 +1258,8 @@ If FORMAT, also format the current score file."
       ;; We do not respect eval and files atoms from global score
       ;; files.
       (when (and files (not global))
-        (setq lists (apply 'append lists
-                           (mapcar 'gnus-score-load-file
+        (setq lists (apply #'append lists
+                           (mapcar #'gnus-score-load-file
                                    (if adapt-file (cons adapt-file files)
                                      files)))))
       (when (and eval (not global))
@@ -1268,7 +1268,7 @@ If FORMAT, also format the current score file."
       (setq gnus-scores-exclude-files
             (nconc
              (apply
-              'nconc
+              #'nconc
               (mapcar
                (lambda (sfile)
                  (list
@@ -1554,10 +1554,10 @@ If FORMAT, also format the current score file."
               (setq entry (pop entries)
                     header (nth 0 entry)
                     gnus-score-index (nth 1 (assoc header gnus-header-index)))
-              (when (< 0 (apply 'max (mapcar
-                                      (lambda (score)
-                                        (length (gnus-score-get header score)))
-                                      scores)))
+              (when (< 0 (apply #'max (mapcar
+                                       (lambda (score)
+                                         (length (gnus-score-get header score)))
+                                       scores)))
                 (when (if (and gnus-inhibit-slow-scoring
                                (or (eq gnus-inhibit-slow-scoring t)
                                    (and (stringp gnus-inhibit-slow-scoring)
@@ -1574,9 +1574,9 @@ If FORMAT, also format the current score file."
                         ;; Run score-fn
                         (if (eq header 'score-fn)
                             (setq new (gnus-score-func scores trace))
-                        ;; Call the scoring function for this type of "header".
-                        (setq new (funcall (nth 2 entry) scores header
-                                           now expire trace))))
+                          ;; Call the scoring function for this type of "header".
+                          (setq new (funcall (nth 2 entry) scores header
+                                             now expire trace))))
                   (push new news))))
 
             (when (gnus-buffer-live-p gnus-summary-buffer)
@@ -1948,7 +1948,7 @@ score in `gnus-newsgroup-scored' by SCORE."
               gnus-newsgroup-name gnus-adaptive-file-suffix))))
 
       (setq gnus-scores-articles (sort gnus-scores-articles
-                                       'gnus-score-string<)
+                                       #'gnus-score-string<)
             articles gnus-scores-articles)
 
       (erase-buffer)
@@ -2077,7 +2077,7 @@ score in `gnus-newsgroup-scored' by SCORE."
           ;; We cannot string-sort the extra headers list.  *sigh*
           (if (= gnus-score-index 9)
               gnus-scores-articles
-            (sort gnus-scores-articles 'gnus-score-string<))
+            (sort gnus-scores-articles #'gnus-score-string<))
           articles gnus-scores-articles)
 
     (erase-buffer)
@@ -2550,11 +2550,11 @@ score in `gnus-newsgroup-scored' by SCORE."
                    (abbreviate-file-name file))))
         (insert
          (format "\nTotal score: %d"
-                 (apply '+ (mapcar
-                            (lambda (s)
-                              (or (caddr s)
-                                  gnus-score-interactive-default-score))
-                            trace))))
+                 (apply #'+ (mapcar
+                             (lambda (s)
+                               (or (caddr s)
+                                   gnus-score-interactive-default-score))
+                             trace))))
         (insert
          "\n\nQuick help:
 
@@ -2872,7 +2872,7 @@ This includes the score file for the group and all its parents."
            (mapcar (lambda (group)
                      (gnus-score-file-name group gnus-adaptive-file-suffix))
                    (setq all (nreverse all)))
-           (mapcar 'gnus-score-file-name all)))
+           (mapcar #'gnus-score-file-name all)))
     (if (equal prefix "")
         all
       (mapcar
@@ -2912,7 +2912,7 @@ Destroys the current buffer."
             (lambda (file)
               (cons (inline (gnus-score-file-rank file)) file))
             files)))
-      (mapcar 'cdr (sort alist 'car-less-than-car)))))
+      (mapcar #'cdr (sort alist #'car-less-than-car)))))
 
 (defun gnus-score-find-alist (group)
   "Return list of score files for GROUP.
diff --git a/lisp/gnus/gnus-search.el b/lisp/gnus/gnus-search.el
index 44780609af7..636a0d76378 100644
--- a/lisp/gnus/gnus-search.el
+++ b/lisp/gnus/gnus-search.el
@@ -1859,7 +1859,7 @@ Assume \"size\" key is equal to \"larger\"."
                      "No directory found in definition of server %s"
                      server))))
     (apply
-     'vconcat
+     #'vconcat
      (mapcar (lambda (x)
                (let ((group x)
                      artlist)
@@ -1894,7 +1894,7 @@ Assume \"size\" key is equal to \"larger\"."
                                 "Cannot locate directory for group")))
                      (save-excursion
                        (apply
-                        'call-process "find" nil t
+                        #'call-process "find" nil t
                         "find" group "-maxdepth" "1" "-type" "f"
                         "-name" "[0-9]*" "-exec"
                         (slot-value engine 'grep-program)
@@ -1907,7 +1907,8 @@ Assume \"size\" key is equal to \"larger\"."
                      (let* ((path (split-string
                                    (buffer-substring
                                     (point)
-                                    (line-end-position)) "/" t))
+                                    (line-end-position))
+                                   "/" t))
                             (art (string-to-number (car (last path)))))
                        (while (string= "." (car path))
                          (setq path (cdr path)))
diff --git a/lisp/gnus/gnus-sieve.el b/lisp/gnus/gnus-sieve.el
index 3b79d578644..7046f5949c7 100644
--- a/lisp/gnus/gnus-sieve.el
+++ b/lisp/gnus/gnus-sieve.el
@@ -140,7 +140,7 @@ For example:
 \(gnus-sieve-string-list \\='(\"to\" \"cc\"))
   => \"[\\\"to\\\", \\\"cc\\\"]\"
 "
-  (concat "[\"" (mapconcat 'identity list "\", \"") "\"]"))
+  (concat "[\"" (mapconcat #'identity list "\", \"") "\"]"))
 
 (defun gnus-sieve-test-list (list)
   "Convert an elisp test list to a Sieve test list.
@@ -148,7 +148,7 @@ For example:
 For example:
 \(gnus-sieve-test-list \\='((address \"sender\" \"boss@company.com\") (size :over 4K)))
   => \"(address \\\"sender\\\" \\\"boss@company.com\\\", size :over 4K)\""
-  (concat "(" (mapconcat 'gnus-sieve-test list ", ") ")"))
+  (concat "(" (mapconcat #'gnus-sieve-test list ", ") ")"))
 
 ;; FIXME: do proper quoting
 (defun gnus-sieve-test-token (token)
@@ -189,7 +189,7 @@ For example:
                           (size :over 100K))))
   => \"anyof (header :contains [\\\"to\\\", \\\"cc\\\"] \\\"my@address.com\\\",
              size :over 100K)\""
-  (mapconcat 'gnus-sieve-test-token test " "))
+  (mapconcat #'gnus-sieve-test-token test " "))
 
 (defun gnus-sieve-script (&optional method crosspost)
   "Generate a Sieve script based on groups with select method METHOD
@@ -228,7 +228,7 @@ This is returned as a string."
                             "\tstop;\n")
                           "}")
                   script)))))
-    (mapconcat 'identity script "\n")))
+    (mapconcat #'identity script "\n")))
 
 (provide 'gnus-sieve)
 
diff --git a/lisp/gnus/gnus-srvr.el b/lisp/gnus/gnus-srvr.el
index 34e5ceb3f67..deeb28885b8 100644
--- a/lisp/gnus/gnus-srvr.el
+++ b/lisp/gnus/gnus-srvr.el
@@ -581,7 +581,7 @@ The following commands are available:
 (defun gnus-server-add-server (how where)
   (interactive
    (list (intern (gnus-completing-read "Server method"
-                                       (mapcar 'car gnus-valid-select-methods)
+                                       (mapcar #'car gnus-valid-select-methods)
                                        t))
          (read-string "Server name: ")))
   (when (assq where gnus-server-alist)
@@ -592,7 +592,8 @@ The following commands are available:
 (defun gnus-server-goto-server (server)
   "Jump to a server line."
   (interactive
-   (list (gnus-completing-read "Goto server" (mapcar 'car gnus-server-alist) t)))
+   (list (gnus-completing-read "Goto server"
+                               (mapcar #'car gnus-server-alist) t)))
   (let ((to (text-property-any (point-min) (point-max)
                                'gnus-server (intern server))))
     (when to
diff --git a/lisp/gnus/gnus-start.el b/lisp/gnus/gnus-start.el
index cf37a1ccdfc..cd438764133 100644
--- a/lisp/gnus/gnus-start.el
+++ b/lisp/gnus/gnus-start.el
@@ -259,7 +259,7 @@ not match this regexp will be removed before saving the list."
                 regexp))
 
 (defcustom gnus-ignored-newsgroups
-  (mapconcat 'identity
+  (mapconcat #'identity
              '("^to\\."                 ; not "real" groups
                "^[0-9. \t]+\\( \\|$\\)" ; all digits in name
                "^[\"][\"#'()]"  ; bogus characters
@@ -518,7 +518,7 @@ Can be used to turn version control on or off."
 ;; For subscribing new newsgroup
 
 (defun gnus-subscribe-hierarchical-interactive (groups)
-  (let ((groups (sort groups 'string<))
+  (let ((groups (sort groups #'string<))
         prefixes prefix start ans group starts)
     (while groups
       (setq prefixes (list "^"))
@@ -3162,7 +3162,7 @@ SPECIFIC-VARIABLES, or those in `gnus-variable-list'."
   "Declare back end NAME with ABILITIES as a Gnus back end."
   (setq gnus-valid-select-methods
         (nconc gnus-valid-select-methods
-               (list (apply 'list name abilities))))
+               (list (apply #'list name abilities))))
   (gnus-redefine-select-method-widget))
 
 (defun gnus-set-default-directory ()
diff --git a/lisp/gnus/gnus-topic.el b/lisp/gnus/gnus-topic.el
index 8a77c532d29..402de05210e 100644
--- a/lisp/gnus/gnus-topic.el
+++ b/lisp/gnus/gnus-topic.el
@@ -335,7 +335,7 @@ If RECURSIVE is t, return groups in its subtopics too."
     (setq topology gnus-topic-topology
           gnus-tmp-topics nil))
   (push (caar topology) gnus-tmp-topics)
-  (mapc 'gnus-topic-list (cdr topology))
+  (mapc #'gnus-topic-list (cdr topology))
   gnus-tmp-topics)
 
 ;;; Topic parameter jazz
@@ -386,7 +386,7 @@ inheritance."
          ;; We probably have lots of nil elements here, so we remove them.
          ;; Probably faster than doing this "properly".
          (delq nil (cons group-params-list
-                         (mapcar 'gnus-topic-parameters
+                         (mapcar #'gnus-topic-parameters
                                  (gnus-current-topics topic)))))
         param out params)
     ;; Now we have all the parameters, so we go through them
@@ -445,7 +445,7 @@ If LOWEST is non-nil, list all newsgroups of level LOWEST or higher."
               (and (>= level gnus-level-zombie)
                    (<= lowest gnus-level-zombie)))
       (gnus-group-prepare-flat-list-dead
-       (setq gnus-zombie-list (sort gnus-zombie-list 'string<))
+       (setq gnus-zombie-list (sort gnus-zombie-list #'string<))
        gnus-level-zombie ?Z
        regexp))
 
@@ -453,7 +453,7 @@ If LOWEST is non-nil, list all newsgroups of level LOWEST or higher."
                (and (>= level gnus-level-killed)
                     (<= lowest gnus-level-killed)))
       (gnus-group-prepare-flat-list-dead
-       (setq gnus-killed-list (sort gnus-killed-list 'string<))
+       (setq gnus-killed-list (sort gnus-killed-list #'string<))
        gnus-level-killed ?K regexp)
       (when not-in-list
         (unless gnus-killed-hashtb
@@ -841,7 +841,7 @@ articles in the topic and its subtopics."
       (pop topics)))
   ;; Go through all living groups and make sure that
   ;; they belong to some topic.
-  (let* ((tgroups (apply 'append (mapcar 'cdr gnus-topic-alist)))
+  (let* ((tgroups (apply #'append (mapcar #'cdr gnus-topic-alist)))
          (entry (last (assoc (caar gnus-topic-topology) gnus-topic-alist)))
          (groups (cdr gnus-group-list)))
     (dolist (group groups)
@@ -1128,21 +1128,21 @@ articles in the topic and its subtopics."
       (when (gnus-visual-p 'topic-menu 'menu)
         (gnus-topic-make-menu-bar))
       (gnus-set-format 'topic t)
-      (add-hook 'gnus-group-catchup-group-hook 'gnus-topic-update-topic)
+      (add-hook 'gnus-group-catchup-group-hook #'gnus-topic-update-topic)
       (setq-local gnus-group-prepare-function
-                  'gnus-group-prepare-topics)
+                  #'gnus-group-prepare-topics)
       (setq-local gnus-group-get-parameter-function
-                  'gnus-group-topic-parameters)
+                  #'gnus-group-topic-parameters)
       (setq-local gnus-group-goto-next-group-function
-                  'gnus-topic-goto-next-group)
+                  #'gnus-topic-goto-next-group)
       (setq-local gnus-group-indentation-function
-                  'gnus-topic-group-indentation)
+                  #'gnus-topic-group-indentation)
       (setq-local gnus-group-update-group-function
-                  'gnus-topic-update-topics-containing-group)
-      (setq-local gnus-group-sort-alist-function 'gnus-group-sort-topic)
-      (setq gnus-group-change-level-function 'gnus-topic-change-level)
-      (setq gnus-goto-missing-group-function 'gnus-topic-goto-missing-group)
-      (add-hook 'gnus-check-bogus-groups-hook 'gnus-topic-clean-alist
+                  #'gnus-topic-update-topics-containing-group)
+      (setq-local gnus-group-sort-alist-function #'gnus-group-sort-topic)
+      (setq gnus-group-change-level-function #'gnus-topic-change-level)
+      (setq gnus-goto-missing-group-function #'gnus-topic-goto-missing-group)
+      (add-hook 'gnus-check-bogus-groups-hook #'gnus-topic-clean-alist
                 nil 'local)
       (setq gnus-topology-checked-p nil)
       ;; We check the topology.
@@ -1150,11 +1150,11 @@ articles in the topic and its subtopics."
         (gnus-topic-check-topology)))
     ;; Remove topic infestation.
     (unless gnus-topic-mode
-      (remove-hook 'gnus-summary-exit-hook 'gnus-topic-update-topic)
+      (remove-hook 'gnus-summary-exit-hook #'gnus-topic-update-topic)
       (setq gnus-group-change-level-function nil)
-      (remove-hook 'gnus-check-bogus-groups-hook 'gnus-topic-clean-alist)
-      (setq gnus-group-prepare-function 'gnus-group-prepare-flat)
-      (setq gnus-group-sort-alist-function 'gnus-group-sort-flat))
+      (remove-hook 'gnus-check-bogus-groups-hook #'gnus-topic-clean-alist)
+      (setq gnus-group-prepare-function #'gnus-group-prepare-flat)
+      (setq gnus-group-sort-alist-function #'gnus-group-sort-flat))
     (when (called-interactively-p 'any)
       (gnus-group-list-groups))))
 
@@ -1213,7 +1213,7 @@ Also see `gnus-group-catchup'."
              (inhibit-read-only t)
              (gnus-group-marked groups))
         (gnus-group-catchup-current)
-        (mapcar 'gnus-topic-update-topics-containing-group groups)))))
+        (mapcar #'gnus-topic-update-topics-containing-group groups)))))
 
 (defun gnus-topic-read-group (&optional all no-article group)
   "Read news in this newsgroup.
@@ -1280,7 +1280,7 @@ When used interactively, PARENT will be the topic under point."
 If COPYP, copy the groups instead."
   (interactive
    (list current-prefix-arg
-         (gnus-completing-read "Move to topic" (mapcar 'car gnus-topic-alist) t
+         (gnus-completing-read "Move to topic" (mapcar #'car gnus-topic-alist) t
                                nil 'gnus-topic-history)))
   (let ((use-marked (and (not n) (not (and transient-mark-mode mark-active))
                          gnus-group-marked t))
@@ -1328,7 +1328,7 @@ If COPYP, copy the groups instead."
   (interactive
    (list current-prefix-arg
          (gnus-completing-read
-          "Copy to topic" (mapcar 'car gnus-topic-alist) t)))
+          "Copy to topic" (mapcar #'car gnus-topic-alist) t)))
   (gnus-topic-move-group n topic t))
 
 (defun gnus-topic-kill-group (&optional n discard)
@@ -1422,7 +1422,7 @@ If PERMANENT, make it stay shown in subsequent sessions as well."
       (let ((topic
              (gnus-topic-find-topology
               (gnus-completing-read "Show topic"
-                                    (mapcar 'car gnus-topic-alist) t))))
+                                    (mapcar #'car gnus-topic-alist) t))))
         (setcar (cddr (cadr topic)) nil)
         (setcar (cdr (cadr topic)) 'visible)
         (gnus-group-list-groups)))))
@@ -1471,7 +1471,7 @@ If NON-RECURSIVE (which is the prefix) is t, don't unmark its subtopics."
      (nreverse
       (list
        (setq topic (gnus-completing-read "Move to topic"
-                                         (mapcar 'car gnus-topic-alist) t))
+                                         (mapcar #'car gnus-topic-alist) t))
        (read-string (format "Move to %s (regexp): " topic))))))
   (gnus-group-mark-regexp regexp)
   (gnus-topic-move-group nil topic copyp))
@@ -1704,7 +1704,7 @@ If REVERSE, sort in reverse order."
 If REVERSE, reverse the sorting order."
   (interactive
    (list (gnus-completing-read "Sort topics in"
-                               (mapcar 'car gnus-topic-alist) t
+                               (mapcar #'car gnus-topic-alist) t
                                (gnus-current-topic))
          current-prefix-arg))
   (let ((topic-topology (or (and topic (cdr (gnus-topic-find-topology topic)))
@@ -1719,7 +1719,7 @@ If REVERSE, reverse the sorting order."
   (interactive
    (list
     (gnus-group-topic-name)
-    (gnus-completing-read "Move to topic" (mapcar 'car gnus-topic-alist) t)))
+    (gnus-completing-read "Move to topic" (mapcar #'car gnus-topic-alist) t)))
   (unless (and current to)
     (error "Can't find topic"))
   (let ((current-top (cdr (gnus-topic-find-topology current)))
diff --git a/lisp/gnus/gnus-undo.el b/lisp/gnus/gnus-undo.el
index 5e72effa6c7..5d2f85af36c 100644
--- a/lisp/gnus/gnus-undo.el
+++ b/lisp/gnus/gnus-undo.el
@@ -103,7 +103,7 @@
     ;; Set up the menu.
     (when (gnus-visual-p 'undo-menu 'menu)
       (gnus-undo-make-menu-bar))
-    (add-hook 'post-command-hook 'gnus-undo-boundary nil t)))
+    (add-hook 'post-command-hook #'gnus-undo-boundary nil t)))
 
 ;;; Interface functions.
 
@@ -161,15 +161,15 @@ A numeric argument serves as a repeat count."
   (unless gnus-undo-mode
     (error "Undoing is not enabled in this buffer"))
   (message "%s" last-command)
-  (when (or (not (eq last-command 'gnus-undo))
-            (not gnus-undo-last))
+  (unless (and (eq last-command 'gnus-undo)
+               gnus-undo-last)
     (setq gnus-undo-last gnus-undo-actions))
   (let ((action (pop gnus-undo-last)))
     (unless action
       (error "Nothing further to undo"))
     (setq gnus-undo-actions (delq action gnus-undo-actions))
     (setq gnus-undo-boundary t)
-    (mapc 'funcall action)))
+    (mapc #'funcall action)))
 
 (provide 'gnus-undo)
 
diff --git a/lisp/gnus/gnus-util.el b/lisp/gnus/gnus-util.el
index 82c8731b471..b8451028d1e 100644
--- a/lisp/gnus/gnus-util.el
+++ b/lisp/gnus/gnus-util.el
@@ -445,7 +445,7 @@ displayed in the echo area."
       `(let (str time)
          (cond ((eq gnus-add-timestamp-to-message 'log)
                 (setq str (let (message-log-max)
-                            (apply 'message ,format-string ,args)))
+                            (apply #'message ,format-string ,args)))
                 (when (and message-log-max
                            (> message-log-max 0)
                            (/= (length str) 0))
@@ -471,7 +471,7 @@ displayed in the echo area."
                   (message "%s" (concat ,timestamp str))
                   str))
                (t
-                (apply 'message ,format-string ,args)))))))
+                (apply #'message ,format-string ,args)))))))
 
 (defvar gnus-action-message-log nil)
 
@@ -491,8 +491,8 @@ inside loops."
   (if (<= level gnus-verbose)
       (let ((message
              (if gnus-add-timestamp-to-message
-                 (apply 'gnus-message-with-timestamp args)
-               (apply 'message args))))
+                 (apply #'gnus-message-with-timestamp args)
+               (apply #'message args))))
         (when (and (consp gnus-action-message-log)
                    (<= level 3))
           (push message gnus-action-message-log))
@@ -513,7 +513,7 @@ inside loops."
   "Beep an error if LEVEL is equal to or less than `gnus-verbose'.
 ARGS are passed to `message'."
   (when (<= (floor level) gnus-verbose)
-    (apply 'message args)
+    (apply #'message args)
     (ding)
     (let (duration)
       (when (and (floatp level)
@@ -1053,16 +1053,16 @@ ARG is passed to the first function."
 (defun gnus-run-hooks (&rest funcs)
   "Does the same as `run-hooks', but saves the current buffer."
   (save-current-buffer
-    (apply 'run-hooks funcs)))
+    (apply #'run-hooks funcs)))
 
 (defun gnus-run-hook-with-args (hook &rest args)
   "Does the same as `run-hook-with-args', but saves the current buffer."
   (save-current-buffer
-    (apply 'run-hook-with-args hook args)))
+    (apply #'run-hook-with-args hook args)))
 
 (defun gnus-run-mode-hooks (&rest funcs)
   "Run `run-mode-hooks', saving the current buffer."
-  (save-current-buffer (apply 'run-mode-hooks funcs)))
+  (save-current-buffer (apply #'run-mode-hooks funcs)))
 
 ;;; Various
 
@@ -1355,7 +1355,7 @@ SPEC is a predicate specifier that contains stuff like `or', `and',
     `(,spec elem))
    ((listp spec)
     (if (memq (car spec) '(or and not))
-        `(,(car spec) ,@(mapcar 'gnus-make-predicate-1 (cdr spec)))
+        `(,(car spec) ,@(mapcar #'gnus-make-predicate-1 (cdr spec)))
       (error "Invalid predicate specifier: %s" spec)))))
 
 (defun gnus-completing-read (prompt collection &optional require-match
@@ -1684,7 +1684,7 @@ lists of strings."
       (setq props (plist-put props :foreground (face-foreground face)))
       (setq props (plist-put props :background (face-background face))))
     (ignore-errors
-      (apply 'create-image file type data-p props))))
+      (apply #'create-image file type data-p props))))
 
 (defun gnus-put-image (glyph &optional string category)
   (let ((point (point)))
diff --git a/lisp/gnus/gnus-uu.el b/lisp/gnus/gnus-uu.el
index db0ffc6d0df..2bc1f864deb 100644
--- a/lisp/gnus/gnus-uu.el
+++ b/lisp/gnus/gnus-uu.el
@@ -356,7 +356,7 @@ didn't work, and overwrite existing files.  Otherwise, ask each time."
 (defun gnus-uu-decode-uu (&optional n)
   "Uudecodes the current article."
   (interactive "P")
-  (gnus-uu-decode-with-method 'gnus-uu-uustrip-article n))
+  (gnus-uu-decode-with-method #'gnus-uu-uustrip-article n))
 
 (defun gnus-uu-decode-uu-and-save (n dir)
   "Decodes and saves the resulting file."
@@ -366,12 +366,12 @@ didn't work, and overwrite existing files.  Otherwise, ask each time."
           (read-directory-name "Uudecode and save in dir: "
                           gnus-uu-default-dir
                           gnus-uu-default-dir t))))
-  (gnus-uu-decode-with-method 'gnus-uu-uustrip-article n dir nil nil t))
+  (gnus-uu-decode-with-method #'gnus-uu-uustrip-article n dir nil nil t))
 
 (defun gnus-uu-decode-unshar (&optional n)
   "Unshars the current article."
   (interactive "P")
-  (gnus-uu-decode-with-method 'gnus-uu-unshar-article n nil nil 'scan t))
+  (gnus-uu-decode-with-method #'gnus-uu-unshar-article n nil nil 'scan t))
 
 (defun gnus-uu-decode-unshar-and-save (n dir)
   "Unshars and saves the current article."
@@ -381,7 +381,7 @@ didn't work, and overwrite existing files.  Otherwise, ask each time."
           (read-directory-name "Unshar and save in dir: "
                           gnus-uu-default-dir
                           gnus-uu-default-dir t))))
-  (gnus-uu-decode-with-method 'gnus-uu-unshar-article n dir nil 'scan t))
+  (gnus-uu-decode-with-method #'gnus-uu-unshar-article n dir nil 'scan t))
 
 (defun gnus-uu-decode-save (n file)
   "Saves the current article."
@@ -393,7 +393,7 @@ didn't work, and overwrite existing files.  Otherwise, ask each time."
            (read-file-name
             "Save article in file: " gnus-uu-default-dir gnus-uu-default-dir))))
   (setq gnus-uu-saved-article-name file)
-  (gnus-uu-decode-with-method 'gnus-uu-save-article n nil t))
+  (gnus-uu-decode-with-method #'gnus-uu-save-article n nil t))
 
 (defun gnus-uu-decode-binhex (n dir)
   "Unbinhexes the current article."
@@ -406,7 +406,7 @@ didn't work, and overwrite existing files.  Otherwise, ask each time."
   (gnus-uu-initialize)
   (setq gnus-uu-binhex-article-name
         (make-temp-file (expand-file-name "binhex" gnus-uu-work-dir)))
-  (gnus-uu-decode-with-method 'gnus-uu-binhex-article n dir))
+  (gnus-uu-decode-with-method #'gnus-uu-binhex-article n dir))
 
 (defun gnus-uu-decode-yenc (n dir)
   "Decode the yEnc-encoded current article."
@@ -417,7 +417,7 @@ didn't work, and overwrite existing files.  Otherwise, ask each time."
                           gnus-uu-default-dir
                           gnus-uu-default-dir))))
   (setq gnus-uu-yenc-article-name nil)
-  (gnus-uu-decode-with-method 'gnus-uu-yenc-article n dir nil t))
+  (gnus-uu-decode-with-method #'gnus-uu-yenc-article n dir nil t))
 
 (defun gnus-uu-decode-uu-view (&optional n)
   "Uudecodes and views the current article."
@@ -729,7 +729,7 @@ When called interactively, prompt for REGEXP."
 (defun gnus-uu-decode-postscript (&optional n)
   "Gets PostScript of the current article."
   (interactive "P")
-  (gnus-uu-decode-with-method 'gnus-uu-decode-postscript-article n))
+  (gnus-uu-decode-with-method #'gnus-uu-decode-postscript-article n))
 
 (defun gnus-uu-decode-postscript-view (&optional n)
   "Gets and views the current article."
@@ -745,7 +745,7 @@ When called interactively, prompt for REGEXP."
           (read-directory-name "Save in dir: "
                           gnus-uu-default-dir
                           gnus-uu-default-dir t))))
-  (gnus-uu-decode-with-method 'gnus-uu-decode-postscript-article
+  (gnus-uu-decode-with-method #'gnus-uu-decode-postscript-article
                               n dir nil nil t))
 
 (defun gnus-uu-decode-postscript-and-save-view (n dir)
@@ -1196,11 +1196,11 @@ When called interactively, prompt for REGEXP."
 
         ;; Expand numbers, sort, and return the list of article
         ;; numbers.
-        (mapcar 'cdr
+        (mapcar #'cdr
                 (sort (gnus-uu-expand-numbers
                        list-of-subjects
                        (not do-not-translate))
-                      'gnus-uu-string<))))))
+                      #'gnus-uu-string<))))))
 
 (defun gnus-uu-expand-numbers (string-list &optional translate)
   ;; Takes a list of strings and "expands" all numbers in all the
@@ -1830,8 +1830,8 @@ Gnus might fail to display all of it.")
 
 ;; Initializing
 
-(add-hook 'gnus-summary-prepare-exit-hook 'gnus-uu-clean-up)
-(add-hook 'gnus-summary-prepare-exit-hook 'gnus-uu-delete-work-dir)
+(add-hook 'gnus-summary-prepare-exit-hook #'gnus-uu-clean-up)
+(add-hook 'gnus-summary-prepare-exit-hook #'gnus-uu-delete-work-dir)
 
 
 
diff --git a/lisp/gnus/gnus.el b/lisp/gnus/gnus.el
index 3b172db2111..1eff9a82230 100644
--- a/lisp/gnus/gnus.el
+++ b/lisp/gnus/gnus.el
@@ -3501,7 +3501,7 @@ You should probably use `gnus-find-method-for-group' instead."
     (while (setq info (pop alist))
       (when (gnus-server-equal (gnus-info-method info) server)
         (push (gnus-info-group info) groups)))
-    (sort groups 'string<)))
+    (sort groups #'string<)))
 
 (defun gnus-group-foreign-p (group)
   "Say whether a group is foreign or not."
diff --git a/lisp/gnus/mail-source.el b/lisp/gnus/mail-source.el
index 91671016a8b..c954f657936 100644
--- a/lisp/gnus/mail-source.el
+++ b/lisp/gnus/mail-source.el
@@ -462,21 +462,23 @@ the `mail-source-keyword-map' variable."
            (cond
             ((and
              (eq keyword :user)
-             (setq user-auth (plist-get
-                              ;; cache the search result in `found'
-                              (or found
-                                  (setq found (nth 0 (apply 'auth-source-search
-                                                            search))))
-                              :user)))
+             (setq user-auth
+                   (plist-get
+                    ;; cache the search result in `found'
+                    (or found
+                        (setq found (nth 0 (apply #'auth-source-search
+                                                  search))))
+                    :user)))
              user-auth)
             ((and
               (eq keyword :password)
-              (setq pass-auth (plist-get
-                               ;; cache the search result in `found'
-                               (or found
-                                   (setq found (nth 0 (apply 'auth-source-search
-                                                             search))))
-                               :secret)))
+              (setq pass-auth
+                    (plist-get
+                     ;; cache the search result in `found'
+                     (or found
+                         (setq found (nth 0 (apply #'auth-source-search
+                                                   search))))
+                     :secret)))
              ;; maybe set the password to the return of the :secret function
              (if (functionp pass-auth)
                  (setq pass-auth (funcall pass-auth))
@@ -685,7 +687,7 @@ Deleting old (> %s day(s)) incoming mail file `%s'." diff bfile)
                       ;; find "our" movemail in exec-directory.
                       ;; Bug#31737
                       (apply
-                       'call-process
+                       #'call-process
                        (append
                         (list
                          mail-source-movemail-program
@@ -1002,11 +1004,11 @@ This only works when `display-time' is enabled."
                  #'mail-source-start-idle-timer))
           ;; When you get new mail, clear "Mail" from the mode line.
           (add-hook 'nnmail-post-get-new-mail-hook
-                    'display-time-event-handler)
+                    #'display-time-event-handler)
           (message "Mail check enabled"))
       (setq display-time-mail-function nil)
       (remove-hook 'nnmail-post-get-new-mail-hook
-                   'display-time-event-handler)
+                   #'display-time-event-handler)
       (message "Mail check disabled"))))
 
 (defun mail-source-fetch-maildir (source callback)
diff --git a/lisp/gnus/message.el b/lisp/gnus/message.el
index 1409a4384ab..3f671193a29 100644
--- a/lisp/gnus/message.el
+++ b/lisp/gnus/message.el
@@ -2195,10 +2195,11 @@ see `message-narrow-to-headers-or-head'."
   (require 'gnus-sum)                   ; for gnus-list-identifiers
   (let ((regexp (if (stringp gnus-list-identifiers)
                     gnus-list-identifiers
-                  (mapconcat 'identity gnus-list-identifiers " *\\|"))))
+                  (mapconcat #'identity gnus-list-identifiers " *\\|"))))
     (if (and (not (equal regexp ""))
              (string-match (concat "\\(\\(\\(Re: +\\)?\\(" regexp
-                                   " *\\)\\)+\\(Re: +\\)?\\)") subject))
+                                   " *\\)\\)+\\(Re: +\\)?\\)")
+                           subject))
         (concat (substring subject 0 (match-beginning 1))
                 (or (match-string 3 subject)
                     (match-string 5 subject))
@@ -3173,7 +3174,7 @@ Like `text-mode', but with these additional commands:
 
 (defun message-setup-fill-variables ()
   "Setup message fill variables."
-  (setq-local fill-paragraph-function 'message-fill-paragraph)
+  (setq-local fill-paragraph-function #'message-fill-paragraph)
   (make-local-variable 'adaptive-fill-first-line-regexp)
   (let ((quote-prefix-regexp
          ;; User should change message-cite-prefix-regexp if
@@ -3197,7 +3198,7 @@ Like `text-mode', but with these additional commands:
                 (concat quote-prefix-regexp "\\|"
                         adaptive-fill-first-line-regexp)))
   (setq-local auto-fill-inhibit-regexp nil)
-  (setq-local normal-auto-fill-function 'message-do-auto-fill))
+  (setq-local normal-auto-fill-function #'message-do-auto-fill))
 
 
 
@@ -4064,7 +4065,7 @@ This function uses `mail-citation-hook' if that is non-nil."
             ;; Insert a blank line if it is peeled off.
             (insert "\n"))))
       (goto-char start)
-      (mapc 'funcall functions)
+      (mapc #'funcall functions)
       (when message-citation-line-function
         (unless (bolp)
           (insert "\n"))
@@ -4555,7 +4556,7 @@ An address might be bogus if there's a matching entry in
                       (and message-bogus-addresses
                            (let ((re
                                   (if (listp message-bogus-addresses)
-                                      (mapconcat 'identity
+                                      (mapconcat #'identity
                                                  message-bogus-addresses
                                                  "\\|")
                                     message-bogus-addresses)))
@@ -4950,7 +4951,7 @@ that instead."
           (let* ((default-directory "/")
                  (coding-system-for-write message-send-coding-system)
                  (cpr (apply
-                       'call-process-region
+                       #'call-process-region
                        (append
                         (list (point-min) (point-max) sendmail-program
                               nil errbuf nil "-oi")
@@ -5002,7 +5003,7 @@ to find out how to use this."
   (pcase
       (let ((coding-system-for-write message-send-coding-system))
         (apply
-         'call-process-region (point-min) (point-max)
+         #'call-process-region (point-min) (point-max)
          message-qmail-inject-program nil nil nil
          ;; qmail-inject's default behavior is to look for addresses on the
          ;; command line; if there're none, it scans the headers.
@@ -5394,7 +5395,7 @@ Otherwise, generate and save a value for `canlock-password' first."
            "Really use %s possibly unknown group%s: %s? "
            (if (= (length errors) 1) "this" "these")
            (if (= (length errors) 1) "" "s")
-           (mapconcat 'identity errors ", "))))
+           (mapconcat #'identity errors ", "))))
         ;; There were no errors.
         ((not errors)
          t)
@@ -6061,7 +6062,7 @@ subscribed address (and not the additional To and Cc header contents)."
          (cc (message-fetch-field "cc"))
          (msg-recipients (concat to (and to cc ", ") cc))
          (recipients
-          (mapcar 'mail-strip-quoted-names
+          (mapcar #'mail-strip-quoted-names
                   (message-tokenize-header msg-recipients)))
          (file-regexps
           (if message-subscribed-address-file
@@ -6078,11 +6079,11 @@ subscribed address (and not the additional To and Cc header contents)."
                       (if re (setq re (concat re "\\|" item))
                         (setq re (concat "\\`\\(" item))))
                     (and re (list (concat re "\\)\\'"))))))))
-         (mft-regexps (apply 'append message-subscribed-regexps
-                             (mapcar 'regexp-quote
+         (mft-regexps (apply #'append message-subscribed-regexps
+                             (mapcar #'regexp-quote
                                      message-subscribed-addresses)
                              file-regexps
-                             (mapcar 'funcall
+                             (mapcar #'funcall
                                      message-subscribed-address-functions))))
     (save-match-data
       (let ((list
@@ -6103,7 +6104,7 @@ subscribed address (and not the additional To and Cc header contents)."
       (dolist (rhs
                (delete-dups
                 (mapcar (lambda (rhs) (or (cadr (split-string rhs "@")) ""))
-                        (mapcar 'downcase
+                        (mapcar #'downcase
                                 (mapcar
                                  (lambda (elem)
                                    (or (cadr elem)
@@ -6569,7 +6570,7 @@ moved to the beginning "
              (if to
                  (concat " to "
                          (or (car (mail-extract-address-components to))
-                             to) "")
+                             to))
                "")
              (if (and group (not (string= group ""))) (concat " on " group) "")
              "*")))
@@ -6583,7 +6584,7 @@ moved to the beginning "
              (if to
                  (concat " to "
                          (or (car (mail-extract-address-components to))
-                             to) "")
+                             to))
                "")
              (if (and group (not (string= group ""))) (concat " on " group) "")
              "*")))
@@ -6612,7 +6613,7 @@ moved to the beginning "
                         (cons (string-to-number (or (match-string 1 b) "1"))
                               b)))
                     (buffer-list)))
-             'car-less-than-car)))
+             #'car-less-than-car)))
           new)))))
 
 (defun message-pop-to-buffer (name &optional switch-function)
@@ -6968,8 +6969,8 @@ The function is called with one parameter, a cons cell ..."
                         (message-fetch-field "original-to")))
             cc (message-fetch-field "cc")
             extra (when message-extra-wide-headers
-                    (mapconcat 'identity
-                               (mapcar 'message-fetch-field
+                    (mapconcat #'identity
+                               (mapcar #'message-fetch-field
                                        message-extra-wide-headers)
                                ", "))
             mct (message-fetch-field "mail-copies-to")
@@ -7053,7 +7054,7 @@ want to get rid of this query permanently.")))
       (setq recipients
             (cond ((functionp message-dont-reply-to-names)
                    (mapconcat
-                    'identity
+                    #'identity
                     (delq nil
                           (mapcar (lambda (mail)
                                     (unless (funcall message-dont-reply-to-names
@@ -7087,7 +7088,7 @@ want to get rid of this query permanently.")))
       ;; Remove hierarchical lists that are contained within each other,
       ;; if message-hierarchical-addresses is defined.
       (when message-hierarchical-addresses
-        (let ((plain-addrs (mapcar 'car recipients))
+        (let ((plain-addrs (mapcar #'car recipients))
               subaddrs recip)
           (while plain-addrs
             (setq subaddrs (assoc (car plain-addrs)
@@ -8366,7 +8367,7 @@ The following arguments may contain lists of values."
         (with-output-to-temp-buffer " *MESSAGE information message*"
           (with-current-buffer " *MESSAGE information message*"
             (fundamental-mode)
-            (mapc 'princ text)
+            (mapc #'princ text)
             (goto-char (point-min))))
         (funcall ask question))
     (funcall ask question)))
diff --git a/lisp/gnus/mm-archive.el b/lisp/gnus/mm-archive.el
index 635e7f4ee84..6173d86327a 100644
--- a/lisp/gnus/mm-archive.el
+++ b/lisp/gnus/mm-archive.el
@@ -54,10 +54,10 @@
                   (write-region (point-min) (point-max) file nil 'silent)
                   (setq decoder (copy-sequence decoder))
                   (setcar (member "%f" decoder) file)
-                  (apply 'call-process (car decoder) nil nil nil
+                  (apply #'call-process (car decoder) nil nil nil
                          (append (cdr decoder) (list dir)))
                   (delete-file file))
-              (apply 'call-process-region (point-min) (point-max) (car decoder)
+              (apply #'call-process-region (point-min) (point-max) (car decoder)
                      nil (gnus-get-buffer-create "*tnef*")
                      nil (append (cdr decoder) (list dir)))))
           `("multipart/mixed"
diff --git a/lisp/gnus/mm-decode.el b/lisp/gnus/mm-decode.el
index a62e954af3f..02cd6af0c98 100644
--- a/lisp/gnus/mm-decode.el
+++ b/lisp/gnus/mm-decode.el
@@ -40,8 +40,8 @@
 
 (defvar gnus-current-window-configuration)
 
-(add-hook 'gnus-exit-gnus-hook 'mm-destroy-postponed-undisplay-list)
-(add-hook 'gnus-exit-gnus-hook 'mm-temp-files-delete)
+(add-hook 'gnus-exit-gnus-hook #'mm-destroy-postponed-undisplay-list)
+(add-hook 'gnus-exit-gnus-hook #'mm-temp-files-delete)
 
 (defgroup mime-display ()
   "Display of MIME in mail and news articles."
@@ -603,7 +603,7 @@ files left at the next time."
     (if fails
         ;; Schedule the deletion of the files left at the next time.
         (with-file-modes #o600
-          (write-region (concat (mapconcat 'identity (nreverse fails) "\n")
+          (write-region (concat (mapconcat #'identity (nreverse fails) "\n")
                                 "\n")
                         nil cache-file nil 'silent))
       (when (file-exists-p cache-file)
@@ -1081,7 +1081,8 @@ external if displayed external."
             (string= total "\"%s\""))
         (setq uses-stdin nil)
         (push (shell-quote-argument
-               (gnus-map-function mm-path-name-rewrite-functions file)) out))
+               (gnus-map-function mm-path-name-rewrite-functions file))
+              out))
        ((string= total "%t")
         (push (shell-quote-argument (car type-list)) out))
        (t
@@ -1092,7 +1093,7 @@ external if displayed external."
       (push (shell-quote-argument
              (gnus-map-function mm-path-name-rewrite-functions file))
             out))
-    (mapconcat 'identity (nreverse out) "")))
+    (mapconcat #'identity (nreverse out) "")))
 
 (defun mm-remove-parts (handles)
   "Remove the displayed MIME parts represented by HANDLES."
diff --git a/lisp/gnus/mm-url.el b/lisp/gnus/mm-url.el
index 412a4744125..73106a29323 100644
--- a/lisp/gnus/mm-url.el
+++ b/lisp/gnus/mm-url.el
@@ -299,7 +299,7 @@ If `mm-url-use-external' is non-nil, use `mm-url-program'."
                 args (append (cdr item) (list url))))
       (setq program mm-url-program
             args (append mm-url-arguments (list url))))
-    (unless (eq 0 (apply 'call-process program nil t nil args))
+    (unless (eq 0 (apply #'call-process program nil t nil args))
       (error "Couldn't fetch %s" url))))
 
 (defvar mm-url-timeout 30
diff --git a/lisp/gnus/mm-util.el b/lisp/gnus/mm-util.el
index db42bfa4b10..329b9e8884d 100644
--- a/lisp/gnus/mm-util.el
+++ b/lisp/gnus/mm-util.el
@@ -380,7 +380,7 @@ like \"&#128;\" to the euro sign, mainly in html messages."
   "Return the MIME charset corresponding to the given Mule CHARSET."
   (let ((css (sort (sort-coding-systems
                     (find-coding-systems-for-charsets (list charset)))
-                   'mm-sort-coding-systems-predicate))
+                   #'mm-sort-coding-systems-predicate))
         cs mime)
     (while (and (not mime)
                 css)
@@ -501,7 +501,7 @@ charset, and a longer list means no appropriate charset."
              (let ((systems (find-coding-systems-region b e)))
                (when mm-coding-system-priorities
                  (setq systems
-                       (sort systems 'mm-sort-coding-systems-predicate)))
+                       (sort systems #'mm-sort-coding-systems-predicate)))
                (setq systems (delq 'compound-text systems))
                (unless (equal systems '(undecided))
                  (while systems
@@ -751,7 +751,7 @@ decompressed data.  The buffer's multibyteness must be turned off."
             (insert-buffer-substring cur)
             (condition-case err
                 (progn
-                  (unless (memq (apply 'call-process-region
+                  (unless (memq (apply #'call-process-region
                                        (point-min) (point-max)
                                        prog t (list t err-file) nil args)
                                 jka-compr-acceptable-retval-list)
diff --git a/lisp/gnus/mm-view.el b/lisp/gnus/mm-view.el
index 0683703a4ea..266f471a3fd 100644
--- a/lisp/gnus/mm-view.el
+++ b/lisp/gnus/mm-view.el
@@ -274,13 +274,13 @@ This is only used if `mm-inline-large-images' is set to
       (write-region (point-min) (point-max) file nil 'silent))
     (delete-region (point-min) (point-max))
     (unwind-protect
-        (apply 'call-process cmd nil t nil (mapcar 'eval args))
+        (apply #'call-process cmd nil t nil (mapcar (lambda (e) (eval e t)) args))
       (delete-file file))
     (and post-func (funcall post-func))))
 
 (defun mm-inline-wash-with-stdin (post-func cmd &rest args)
   (let ((coding-system-for-write 'binary))
-    (apply 'call-process-region (point-min) (point-max)
+    (apply #'call-process-region (point-min) (point-max)
            cmd t t nil args))
   (and post-func (funcall post-func)))
 
@@ -290,7 +290,7 @@ This is only used if `mm-inline-large-images' is set to
      handle
      (mm-with-unibyte-buffer
        (insert source)
-       (apply 'mm-inline-wash-with-file post-func cmd args)
+       (apply #'mm-inline-wash-with-file post-func cmd args)
        (buffer-string)))))
 
 (defun mm-inline-render-with-stdin (handle post-func cmd &rest args)
@@ -299,7 +299,7 @@ This is only used if `mm-inline-large-images' is set to
      handle
      (mm-with-unibyte-buffer
        (insert source)
-       (apply 'mm-inline-wash-with-stdin post-func cmd args)
+       (apply #'mm-inline-wash-with-stdin post-func cmd args)
        (buffer-string)))))
 
 (defun mm-inline-render-with-function (handle func &rest args)
@@ -317,7 +317,7 @@ This is only used if `mm-inline-large-images' is set to
 
 (defun mm-inline-text-html (handle)
   (if (stringp (car handle))
-      (mapcar 'mm-inline-text-html (cdr handle))
+      (mapcar #'mm-inline-text-html (cdr handle))
     (let* ((func mm-text-html-renderer)
            (entry (assq func mm-text-html-renderer-alist))
            (inhibit-read-only t))
diff --git a/lisp/gnus/mml-sec.el b/lisp/gnus/mml-sec.el
index c117a3866ab..a050fe04e1b 100644
--- a/lisp/gnus/mml-sec.el
+++ b/lisp/gnus/mml-sec.el
@@ -236,7 +236,7 @@ You can also customize or set `mml-signencrypt-style-alist' instead."
                  (re-search-forward
                   (concat "^" (regexp-quote mail-header-separator) "\n") nil t))
              (goto-char (match-end 0))
-             (apply 'mml-insert-tag 'part (cons (if sign 'sign 'encrypt)
+             (apply #'mml-insert-tag 'part (cons (if sign 'sign 'encrypt)
                                                 (cons method tags))))
             (t (error "The message is corrupted. No mail header separator"))))))
 
@@ -346,8 +346,8 @@ either an error is raised or not."
               (concat "^" (regexp-quote mail-header-separator) "\n") nil t)
              (goto-char (setq insert-loc (match-end 0)))
              (unless (looking-at "<#secure")
-               (apply 'mml-insert-tag
-                'secure 'method method 'mode mode tags)))
+               (apply #'mml-insert-tag
+                      'secure 'method method 'mode mode tags)))
             (t (error
                 "The message is corrupted. No mail header separator"))))
     (when (eql insert-loc (point))
@@ -558,7 +558,7 @@ Return keys."
   (cl-assert keys)
   (let* ((usage-prefs (mml-secure-cust-usage-lookup context usage))
          (curr-fprs (cdr (assoc name (cdr usage-prefs))))
-         (key-fprs (mapcar 'mml-secure-fingerprint keys))
+         (key-fprs (mapcar #'mml-secure-fingerprint keys))
          (new-fprs (cl-union curr-fprs key-fprs :test 'equal)))
     (if curr-fprs
         (setcdr (assoc name (cdr usage-prefs)) new-fprs)
@@ -795,7 +795,7 @@ When `mml-secure-fail-when-key-problem' is t, fail with an error in case of
 outdated or multiple keys."
   (let* ((nname (mml-secure-normalize-cust-name name))
          (fprs (mml-secure-cust-fpr-lookup context usage nname))
-         (usable-fprs (mapcar 'mml-secure-fingerprint keys)))
+         (usable-fprs (mapcar #'mml-secure-fingerprint keys)))
     (if fprs
         (if (gnus-subsetp fprs usable-fprs)
             (mml-secure-filter-keys keys fprs)
diff --git a/lisp/gnus/mml-smime.el b/lisp/gnus/mml-smime.el
index 5baeaffa53a..e97e3e9a06e 100644
--- a/lisp/gnus/mml-smime.el
+++ b/lisp/gnus/mml-smime.el
@@ -179,7 +179,7 @@ Whether the passphrase is cached at all is controlled by
                 (and from (smime-get-key-by-email from)))
               (smime-get-key-by-email
                (gnus-completing-read "Sign this part with what signature"
-                                     (mapcar 'car smime-keys) nil nil nil
+                                     (mapcar #'car smime-keys) nil nil nil
                                      (and (listp (car-safe smime-keys))
                                           (caar smime-keys))))))))
 
@@ -287,7 +287,7 @@ Whether the passphrase is cached at all is controlled by
                                          (point-min) (point))
                                         addresses)))
               (delete-region (point-min) (point)))
-            (setq addresses (mapcar 'downcase addresses))))
+            (setq addresses (mapcar #'downcase addresses))))
         (if (not (member (downcase (or (mm-handle-multipart-from ctl) ""))
                          addresses))
             (mm-sec-error 'gnus-info "Sender address forged")
@@ -299,7 +299,7 @@ Whether the passphrase is cached at all is controlled by
          (concat "Sender claimed to be: " (mm-handle-multipart-from ctl) "\n"
                  (if addresses
                      (concat "Addresses in certificate: "
-                             (mapconcat 'identity addresses ", "))
+                             (mapconcat #'identity addresses ", "))
                    "No addresses found in certificate. (Requires OpenSSL 0.9.6 or later.)")
                  "\n" "\n"
                  "OpenSSL output:\n"
diff --git a/lisp/gnus/mml.el b/lisp/gnus/mml.el
index 424215de941..752dede8d01 100644
--- a/lisp/gnus/mml.el
+++ b/lisp/gnus/mml.el
@@ -206,8 +206,8 @@ part.  This is for the internal use, you should never modify the value.")
 
 (defun mml-destroy-buffers ()
   (let (kill-buffer-hook)
-    (mapc 'kill-buffer mml-buffer-list)
-    (setq mml-buffer-list nil)))
+    (mapc #'kill-buffer (prog1 mml-buffer-list
+                          (setq mml-buffer-list nil)))))
 
 (defun mml-parse ()
   "Parse the current buffer as an MML document."
@@ -499,7 +499,7 @@ type detected."
                  content-type)
         (setcdr (assq 'type (cdr (car cont))) content-type))
       (when (fboundp 'libxml-parse-html-region)
-        (setq cont (mapcar 'mml-expand-all-html-into-multipart-related cont)))
+        (setq cont (mapcar #'mml-expand-all-html-into-multipart-related cont)))
       (prog1
           (with-temp-buffer
             (set-buffer-multibyte nil)
@@ -862,7 +862,7 @@ type detected."
                                     (cl-incf mml-multipart-number)))
         (throw 'not-unique nil))))
    ((eq (car cont) 'multipart)
-    (mapc 'mml-compute-boundary-1 (cddr cont))))
+    (mapc #'mml-compute-boundary-1 (cddr cont))))
   t)
 
 (defun mml-make-boundary (number)
@@ -1077,7 +1077,7 @@ If HANDLES is non-nil, use it instead reparsing the buffer."
       (goto-char (point-max))
       (insert "<#/mml>\n"))
      ((stringp (car handle))
-      (mapc 'mml-insert-mime (cdr handle))
+      (mapc #'mml-insert-mime (cdr handle))
       (insert "<#/multipart>\n"))
      (textp
       (let ((charset (mail-content-type-get
diff --git a/lisp/gnus/nnagent.el b/lisp/gnus/nnagent.el
index f2acea4fa64..1f21eee8680 100644
--- a/lisp/gnus/nnagent.el
+++ b/lisp/gnus/nnagent.el
@@ -138,13 +138,13 @@
                group action server)))
   nil)
 
-(deffoo nnagent-retrieve-headers (articles &optional group server fetch-old)
+(deffoo nnagent-retrieve-headers (articles &optional group _server fetch-old)
   (let ((file (gnus-agent-article-name ".overview" group))
         arts n first)
     (save-excursion
       (gnus-agent-load-alist group)
       (setq arts (gnus-sorted-difference
-                  articles (mapcar 'car gnus-agent-article-alist)))
+                  articles (mapcar #'car gnus-agent-article-alist)))
       ;; Assume that articles with smaller numbers than the first one
       ;; Agent knows are gone.
       (setq first (caar gnus-agent-article-alist))
diff --git a/lisp/gnus/nndiary.el b/lisp/gnus/nndiary.el
index b3e83e494d7..c1ac3cc5e81 100644
--- a/lisp/gnus/nndiary.el
+++ b/lisp/gnus/nndiary.el
@@ -532,8 +532,8 @@ all.  This may very well take some time.")
       (nndiary-possibly-change-directory group server)
       (let ((articles (nnheader-directory-articles nndiary-current-directory)))
         (when articles
-          (setcar active (apply 'min articles))
-          (setcdr active (apply 'max articles))))
+          (setcar active (apply #'min articles))
+          (setcdr active (apply #'max articles))))
       (nnmail-save-active nndiary-group-alist nndiary-active-file)
       (run-hook-with-args 'nndiary-request-create-group-functions
                           (gnus-group-prefixed-name group
@@ -589,7 +589,7 @@ all.  This may very well take some time.")
     (let ((active (nth 1 (assoc group nndiary-group-alist))))
       (when active
         (setcar active (or (and active-articles
-                                (apply 'min active-articles))
+                                (apply #'min active-articles))
                            (1+ (cdr active)))))
       (nnmail-save-active nndiary-group-alist nndiary-active-file))
     (nndiary-save-nov)
@@ -960,7 +960,7 @@ all.  This may very well take some time.")
         (setq nndiary-article-file-alist
               (sort
                (nnheader-article-to-file-alist nndiary-current-directory)
-               'car-less-than-car)))
+               #'car-less-than-car)))
       (setq active
             (if nndiary-article-file-alist
                 (cons (caar nndiary-article-file-alist)
@@ -1055,7 +1055,7 @@ all.  This may very well take some time.")
           (nndiary-generate-nov-databases-1 dir seen))))
     ;; Do this directory.
     (let ((nndiary-files (sort (nnheader-article-to-file-alist dir)
-                       'car-less-than-car)))
+                       #'car-less-than-car)))
       (if (not nndiary-files)
           (let* ((group (nnheader-file-to-group
                          (directory-file-name dir) nndiary-directory))
@@ -1245,7 +1245,7 @@ all.  This may very well take some time.")
 
 (defun nndiary-unflatten (spec)
   ;; opposite of flatten: build ranges if possible
-  (setq spec (sort spec '<))
+  (setq spec (sort spec #'<))
   (let (min max res)
     (while (setq min (pop spec))
       (setq max min)
@@ -1300,7 +1300,7 @@ all.  This may very well take some time.")
                (apply #'encode-time 0 0 0 1 1 (nthcdr 5 date-elts))
                (* (car reminder) 400861056))))
        res))
-    (sort res 'time-less-p)))
+    (sort res #'time-less-p)))
 
 (defun nndiary-last-occurrence (sched)
   ;; Returns the last occurrence of schedule SCHED as an Emacs time struct, or
@@ -1318,8 +1318,8 @@ all.  This may very well take some time.")
       ;; bored in finding a good algorithm for doing that ;-)
       ;; ### FIXME: remove identical entries.
       (let ((dom-list (nth 2 sched))
-            (month-list (sort (nndiary-flatten (nth 3 sched) 1 12) '>))
-            (year-list (sort (nndiary-flatten (nth 4 sched) 1971) '>))
+            (month-list (sort (nndiary-flatten (nth 3 sched) 1 12) #'>))
+            (year-list (sort (nndiary-flatten (nth 4 sched) 1971) #'>))
             (dow-list (nth 5 sched)))
         ;; Special case: an asterisk in one of the days specifications means
         ;; that only the other should be taken into account. If both are
@@ -1370,7 +1370,7 @@ all.  This may very well take some time.")
                        (setq day (+ 7 day))))
                    ;; Finally, if we have some days, they are valid
                    (when days
-                     (sort days '>)
+                     (sort days #'>)
                      (throw 'found
                             (encode-time 0 minute hour
                                          (car days) month year time-zone)))
@@ -1396,12 +1396,12 @@ all.  This may very well take some time.")
          (this-day (decoded-time-day today))
          (this-month (decoded-time-month today))
          (this-year (decoded-time-year today))
-         (minute-list (sort (nndiary-flatten (nth 0 sched) 0 59) '<))
-         (hour-list (sort (nndiary-flatten (nth 1 sched) 0 23) '<))
+         (minute-list (sort (nndiary-flatten (nth 0 sched) 0 59) #'<))
+         (hour-list (sort (nndiary-flatten (nth 1 sched) 0 23) #'<))
          (dom-list (nth 2 sched))
-         (month-list (sort (nndiary-flatten (nth 3 sched) 1 12) '<))
+         (month-list (sort (nndiary-flatten (nth 3 sched) 1 12) #'<))
          (years (if (nth 4 sched)
-                    (sort (nndiary-flatten (nth 4 sched) 1971) '<)
+                    (sort (nndiary-flatten (nth 4 sched) 1971) #'<)
                   t))
          (dow-list (nth 5 sched))
          (year (1- this-year))
@@ -1474,7 +1474,7 @@ all.  This may very well take some time.")
                    ;; Aaaaaaall right. Now we have a valid list of DAYS for
                    ;; this month and this year.
                    (when days
-                     (setq days (sort days '<))
+                     (setq days (sort days #'<))
                      ;; Remove past days for this year and this month.
                      (and (= year this-year)
                           (= month this-month)
diff --git a/lisp/gnus/nndoc.el b/lisp/gnus/nndoc.el
index a3a66454853..c68e2012713 100644
--- a/lisp/gnus/nndoc.el
+++ b/lisp/gnus/nndoc.el
@@ -427,9 +427,9 @@ from the document.")
           (setq result nil))))
     (unless (or result results)
       (error "Document is not of any recognized type"))
-    (if result
-        (car entry)
-      (cadar (last (sort results 'car-less-than-car))))))
+    (car (if result
+             entry
+           (cdar (last (sort results #'car-less-than-car)))))))
 
 ;;;
 ;;; Built-in type predicates and functions
diff --git a/lisp/gnus/nndraft.el b/lisp/gnus/nndraft.el
index 1f87beda5f5..9e70bb62148 100644
--- a/lisp/gnus/nndraft.el
+++ b/lisp/gnus/nndraft.el
@@ -204,8 +204,8 @@ are generated if and only if they are also in `message-draft-headers'."
     (setq buffer-file-name (expand-file-name file)
           buffer-auto-save-file-name (make-auto-save-file-name))
     (clear-visited-file-modtime)
-    (add-hook 'write-contents-functions 'nndraft-generate-headers nil t)
-    (add-hook 'after-save-hook 'nndraft-update-unread-articles nil t)
+    (add-hook 'write-contents-functions #'nndraft-generate-headers nil t)
+    (add-hook 'after-save-hook #'nndraft-update-unread-articles nil t)
     (message-add-action '(nndraft-update-unread-articles)
                         'exit 'postpone 'kill)
     article))
@@ -316,7 +316,7 @@ are generated if and only if they are also in `message-draft-headers'."
           (nnheader-concat nndraft-directory group))))
 
 (defun nndraft-article-filename (article &rest args)
-  (apply 'concat
+  (apply #'concat
          (file-name-as-directory nndraft-current-directory)
          (int-to-string article)
          args))
@@ -334,9 +334,9 @@ are generated if and only if they are also in `message-draft-headers'."
   "Return the list of messages in the group."
   (gnus-make-directory nndraft-current-directory)
   (sort
-   (mapcar 'string-to-number
+   (mapcar #'string-to-number
            (directory-files nndraft-current-directory nil "\\`[0-9]+\\'" t))
-   '<))
+   #'<))
 
 (nnoo-import nndraft
   (nnmh
diff --git a/lisp/gnus/nnfolder.el b/lisp/gnus/nnfolder.el
index 9a0219c1436..405ab2f92f4 100644
--- a/lisp/gnus/nnfolder.el
+++ b/lisp/gnus/nnfolder.el
@@ -145,7 +145,7 @@ all.  This may very well take some time.")
               'nov
             (setq articles (gnus-sorted-intersection
                             ;; Is ARTICLES sorted?
-                            (sort articles '<)
+                            (sort articles #'<)
                             (nnfolder-existing-articles)))
             (while (setq article (pop articles))
               (set-buffer nnfolder-current-buffer)
diff --git a/lisp/gnus/nnheader.el b/lisp/gnus/nnheader.el
index a381720f24c..ae8506c5c20 100644
--- a/lisp/gnus/nnheader.el
+++ b/lisp/gnus/nnheader.el
@@ -468,7 +468,7 @@ leaving the original buffer untouched."
 (defun nnheader-write-overview-file (file headers)
   "Write HEADERS to FILE."
   (with-temp-file file
-    (mapcar 'nnheader-insert-nov headers)))
+    (mapcar #'nnheader-insert-nov headers)))
 
 (defun nnheader-insert-header (header)
   (insert
@@ -723,15 +723,15 @@ an alarming frequency on NFS mounted file systems.  If it is nil,
 
 (defun nnheader-directory-files-safe (&rest args)
   "Execute `directory-files' twice and returns the longer result."
-  (let ((first (apply 'directory-files args))
-        (second (apply 'directory-files args)))
+  (let ((first (apply #'directory-files args))
+        (second (apply #'directory-files args)))
     (if (> (length first) (length second))
         first
       second)))
 
 (defun nnheader-directory-articles (dir)
   "Return a list of all article files in directory DIR."
-  (mapcar 'nnheader-file-to-number
+  (mapcar #'nnheader-file-to-number
           (if nnheader-directory-files-is-safe
               (directory-files
                dir nil nnheader-numerical-short-files t)
@@ -783,7 +783,7 @@ The first string in ARGS can be a format string."
   (set (intern (format "%s-status-string" backend))
        (if (< (length args) 2)
            (car args)
-         (apply 'format args)))
+         (apply #'format args)))
   nil)
 
 (defun nnheader-get-report-string (backend)
@@ -804,8 +804,8 @@ without formatting."
   (with-current-buffer nntp-server-buffer
     (erase-buffer)
     (if (string-match "%" format)
-        (insert (apply 'format format args))
-      (apply 'insert format args))
+        (insert (apply #'format format args))
+      (apply #'insert format args))
     t))
 
 (defsubst nnheader-replace-chars-in-string (string from to)
@@ -841,12 +841,13 @@ without formatting."
 
 (defun nnheader-message (level &rest args)
   "Message if the Gnus backends are talkative."
-  (if (or (not (numberp gnus-verbose-backends))
-          (<= level gnus-verbose-backends))
-      (if gnus-add-timestamp-to-message
-          (apply 'gnus-message-with-timestamp args)
-        (apply 'message args))
-    (apply 'format args)))
+  (apply (cond
+          ((and (numberp gnus-verbose-backends)
+                (> level gnus-verbose-backends))
+           #'format)
+          (gnus-add-timestamp-to-message #'gnus-message-with-timestamp)
+          (t #'message))
+         args))
 
 (defun nnheader-be-verbose (level)
   "Return whether the backends should be verbose on LEVEL."
@@ -877,7 +878,7 @@ without formatting."
 
 (defun nnheader-concat (dir &rest files)
   "Concat DIR as directory to FILES."
-  (apply 'concat (file-name-as-directory dir) files))
+  (apply #'concat (file-name-as-directory dir) files))
 
 (defun nnheader-ms-strip-cr ()
   "Strip ^M from the end of all lines."
@@ -915,7 +916,7 @@ first.  Otherwise, find the newest one, though it may take a time."
         (setq path (cdr path))))
     (if (or first (not (cdr results)))
         (car results)
-      (car (sort results 'file-newer-than-file-p)))))
+      (car (sort results #'file-newer-than-file-p)))))
 
 (defvar ange-ftp-path-format)
 (defvar efs-path-regexp)
@@ -961,15 +962,15 @@ find-file-hook, etc.
   "Open a file with some variables bound.
 See `find-file-noselect' for the arguments."
   (cl-letf* ((format-alist nil)
-          (auto-mode-alist (mm-auto-mode-alist))
-          ((default-value 'major-mode) 'fundamental-mode)
-          (enable-local-variables nil)
-          (after-insert-file-functions nil)
-          (enable-local-eval nil)
-          (coding-system-for-read nnheader-file-coding-system)
-          (version-control 'never)
-          (find-file-hook nil))
-    (apply 'find-file-noselect args)))
+             (auto-mode-alist (mm-auto-mode-alist))
+             ((default-value 'major-mode) 'fundamental-mode)
+             (enable-local-variables nil)
+             (after-insert-file-functions nil)
+             (enable-local-eval nil)
+             (coding-system-for-read nnheader-file-coding-system)
+             (version-control 'never)
+             (find-file-hook nil))
+    (apply #'find-file-noselect args)))
 
 (defun nnheader-directory-regular-files (dir)
   "Return a list of all regular files in DIR."
@@ -983,7 +984,7 @@ See `find-file-noselect' for the arguments."
 
 (defun nnheader-directory-files (&rest args)
   "Same as `directory-files', but prune \".\" and \"..\"."
-  (let ((files (apply 'directory-files args))
+  (let ((files (apply #'directory-files args))
         out)
     (while files
       (unless (member (file-name-nondirectory (car files)) '("." ".."))
@@ -1065,7 +1066,7 @@ See `find-file-noselect' for the arguments."
   (let ((now (current-time)))
     (when (time-less-p 1 (time-subtract now nnheader-last-message-time))
       (setq nnheader-last-message-time now)
-      (apply 'nnheader-message args))))
+      (apply #'nnheader-message args))))
 
 (make-obsolete-variable 'nnheader-load-hook
                         "use `with-eval-after-load' instead." "28.1")
diff --git a/lisp/gnus/nnmail.el b/lisp/gnus/nnmail.el
index d043ae1b426..59d61379f14 100644
--- a/lisp/gnus/nnmail.el
+++ b/lisp/gnus/nnmail.el
@@ -1281,7 +1281,7 @@ Return the number of characters in the body."
   "Remove list identifiers from Subject headers."
   (let ((regexp
          (if (consp nnmail-list-identifiers)
-             (mapconcat 'identity nnmail-list-identifiers " *\\|")
+             (mapconcat #'identity nnmail-list-identifiers " *\\|")
            nnmail-list-identifiers)))
     (when regexp
       (goto-char (point-min))
@@ -1321,8 +1321,8 @@ Eudora has a broken References line, but an OK In-Reply-To."
     (when (re-search-forward "^\\(In-Reply-To:[^\n]+\\)\n[ \t]+" nil t)
       (replace-match "\\1" t))))
 
-(defalias 'nnmail-fix-eudora-headers 'nnmail-ignore-broken-references)
-(make-obsolete 'nnmail-fix-eudora-headers 'nnmail-ignore-broken-references "Emacs 23.1")
+(defalias 'nnmail-fix-eudora-headers #'nnmail-ignore-broken-references)
+(make-obsolete 'nnmail-fix-eudora-headers #'nnmail-ignore-broken-references "Emacs 23.1")
 
 (custom-add-option 'nnmail-prepare-incoming-header-hook
                    'nnmail-ignore-broken-references)
@@ -1528,7 +1528,7 @@ See the documentation for the variable `nnmail-split-fancy' for details."
                   expanded))))
       (setq pos (1+ pos)))
     (if did-expand
-        (apply 'concat (nreverse expanded))
+        (apply #'concat (nreverse expanded))
       newtext)))
 
 ;; Activate a backend only if it isn't already activated.
@@ -1623,7 +1623,7 @@ See the documentation for the variable `nnmail-split-fancy' for details."
                  (gnus-methods-equal-p gnus-command-method
                                        (nnmail-cache-primary-mail-backend)))
             (let ((regexp (if (consp nnmail-cache-ignore-groups)
-                              (mapconcat 'identity nnmail-cache-ignore-groups
+                              (mapconcat #'identity nnmail-cache-ignore-groups
                                          "\\|")
                             nnmail-cache-ignore-groups)))
               (unless (and regexp (string-match regexp grp))
@@ -1766,7 +1766,7 @@ See the Info node `(gnus)Fancy Mail Splitting' for more details."
 (defvar nnmail-fetched-sources nil)
 
 (defun nnmail-get-value (&rest args)
-  (let ((sym (intern (apply 'format args))))
+  (let ((sym (intern (apply #'format args))))
     (when (boundp sym)
       (symbol-value sym))))
 
diff --git a/lisp/gnus/nnmaildir.el b/lisp/gnus/nnmaildir.el
index 4179a2cc633..46691e3494b 100644
--- a/lisp/gnus/nnmaildir.el
+++ b/lisp/gnus/nnmaildir.el
@@ -101,7 +101,7 @@ SUFFIX should start with \":2,\"."
          (new-flags
           (concat (gnus-delete-duplicates
                    ;; maildir flags must be sorted
-                   (sort (cons flag flags-as-list) '<)))))
+                   (sort (cons flag flags-as-list) #'<)))))
     (concat ":2," new-flags)))
 
 (defun nnmaildir--remove-flag (flag suffix)
@@ -292,7 +292,7 @@ This variable is set by `nnmaildir-request-article'.")
   (write-region "" nil file nil 'no-message))
 (defun nnmaildir--delete-dir-files (dir ls)
   (when (file-attributes dir)
-    (mapc 'delete-file (funcall ls dir 'full "\\`[^.]" 'nosort))
+    (mapc #'delete-file (funcall ls dir 'full "\\`[^.]" 'nosort))
     (delete-directory dir)))
 
 (defun nnmaildir--group-maxnum (server group)
@@ -855,8 +855,8 @@ This variable is set by `nnmaildir-request-article'.")
                           file))
                    files)
             files (delq nil files)
-            files (mapcar 'nnmaildir--parse-filename files)
-            files (sort files 'nnmaildir--sort-files))
+            files (mapcar #'nnmaildir--parse-filename files)
+            files (sort files #'nnmaildir--sort-files))
       (dolist (file files)
         (setq file (if (consp file) file (aref file 3))
               x (make-nnmaildir--art :prefix (car file) :suffix (cdr file)))
@@ -998,7 +998,7 @@ This variable is set by `nnmaildir-request-article'.")
             always-marks (nnmaildir--param pgname 'always-marks)
             never-marks (nnmaildir--param pgname 'never-marks)
             existing (nnmaildir--grp-nlist group)
-            existing (mapcar 'car existing)
+            existing (mapcar #'car existing)
             existing (nreverse existing)
             existing (gnus-compress-sequence existing 'always-list)
             missing (list (cons 1 (nnmaildir--group-maxnum
@@ -1013,8 +1013,8 @@ This variable is set by `nnmaildir-request-article'.")
                        ;; get mark names from mark dirs and from flag
                        ;; mappings
                        (append
-                        (mapcar 'cdr nnmaildir-flag-mark-mapping)
-                        (mapcar 'intern (funcall ls dir nil "\\`[^.]" 'nosort))))
+                        (mapcar #'cdr nnmaildir-flag-mark-mapping)
+                        (mapcar #'intern (funcall ls dir nil "\\`[^.]" 'nosort))))
             new-mmth (make-hash-table :size (length all-marks))
             old-mmth (nnmaildir--grp-mmth group))
       (dolist (mark all-marks)
@@ -1070,7 +1070,7 @@ This variable is set by `nnmaildir-request-article'.")
                  (let ((article (nnmaildir--flist-art flist prefix)))
                    (when article
                      (push (nnmaildir--art-num article) article-list))))))
-            (setq ranges (gnus-add-to-range ranges (sort article-list '<)))))
+            (setq ranges (gnus-add-to-range ranges (sort article-list #'<)))))
         (if (eq mark 'read) (setq read ranges)
           (if ranges (setq marks (cons (cons mark ranges) marks)))))
       (setf (gnus-info-read info) (gnus-range-add read missing))
@@ -1695,8 +1695,8 @@ This variable is set by `nnmaildir-request-article'.")
                        ;; get mark names from mark dirs and from flag
                        ;; mappings
                        (append
-                        (mapcar 'cdr nnmaildir-flag-mark-mapping)
-                        (mapcar 'intern all-marks))))
+                        (mapcar #'cdr nnmaildir-flag-mark-mapping)
+                        (mapcar #'intern all-marks))))
       (dolist (action actions)
         (setq ranges (car action)
               todo-marks (caddr action))
diff --git a/lisp/gnus/nnmairix.el b/lisp/gnus/nnmairix.el
index c061031b40a..54d6c5276e4 100644
--- a/lisp/gnus/nnmairix.el
+++ b/lisp/gnus/nnmairix.el
@@ -193,8 +193,8 @@
   (define-key gnus-summary-mode-map
     (kbd "G G u") 'nnmairix-remove-tick-mark-original-article))
 
-(add-hook 'gnus-group-mode-hook 'nnmairix-group-mode-hook)
-(add-hook 'gnus-summary-mode-hook 'nnmairix-summary-mode-hook)
+(add-hook 'gnus-group-mode-hook #'nnmairix-group-mode-hook)
+(add-hook 'gnus-summary-mode-hook #'nnmairix-summary-mode-hook)
 
 ;; ;;;###autoload
 ;; (defun nnmairix-initialize (&optional force)
@@ -202,8 +202,8 @@
 ;;   (if (not (or (file-readable-p "~/.mairixrc")
 ;;             force))
 ;;       (message "No file `~/.mairixrc', skipping nnmairix setup")
-;;     (add-hook 'gnus-group-mode-hook 'nnmairix-group-mode-hook)
-;;     (add-hook 'gnus-summary-mode-hook 'nnmairix-summary-mode-hook)))
+;;     (add-hook 'gnus-group-mode-hook #'nnmairix-group-mode-hook)
+;;     (add-hook 'gnus-summary-mode-hook #'nnmairix-summary-mode-hook)))
 
 ;; Customizable stuff
 
@@ -783,7 +783,7 @@ called interactively, user will be asked for parameters."
         (setq finished (not (y-or-n-p "Add another search query? "))
               achar nil))
     (nnmairix-search
-     (mapconcat 'identity query " ")
+     (mapconcat #'identity query " ")
      (car (nnmairix-get-server))
      (y-or-n-p "Include whole threads? "))))
 
@@ -824,7 +824,7 @@ called interactively, user will be asked for parameters."
     (setq group (read-string "Group name: "))
     (set-buffer gnus-summary-buffer)
     (message "Creating group %s on server %s with query %s." group
-             (gnus-method-to-server server) (mapconcat 'identity query " "))
+             (gnus-method-to-server server) (mapconcat #'identity query " "))
     (nnmairix-create-search-group server group query threads)))
 
 (defun nnmairix-create-server-and-default-group ()
@@ -866,7 +866,7 @@ All necessary information will be queried from the user."
     (if (eq (car method) 'nnmairix)
         (progn
           (when (listp oldquery)
-            (setq oldquery (mapconcat 'identity oldquery " ")))
+            (setq oldquery (mapconcat #'identity oldquery " ")))
           (setq query (or query
                           (read-string "New query: " oldquery)))
           (when (stringp query)
@@ -1068,7 +1068,7 @@ with `nnmairix-mairix-update-options'."
             (if (> (length commandsplit) 1)
                 (setq args (append args (cdr commandsplit) nnmairix-mairix-update-options))
               (setq args (append args nnmairix-mairix-update-options)))
-            (apply 'call-process args)
+            (apply #'call-process args)
             (nnheader-message 7 "Updating mairix database for %s... done" cur))
         (progn
           (setq args (append (list cur (get-buffer nnmairix-mairix-output-buffer)
@@ -1076,7 +1076,7 @@ with `nnmairix-mairix-update-options'."
           (if (> (length commandsplit) 1)
               (setq args (append args (cdr commandsplit) nnmairix-mairix-update-options))
             (setq args (append args nnmairix-mairix-update-options)))
-          (set-process-sentinel (apply 'start-process args)
+          (set-process-sentinel (apply #'start-process args)
                                 'nnmairix-sentinel-mairix-update-finished))))))
 
 (defun nnmairix-group-delete-recreate-this-group ()
@@ -1260,7 +1260,7 @@ If THREADS is non-nil, enable full threads."
         (setq args (append args '("-c"))))
       (when threads
         (setq args (append args '("-t"))))
-      (apply 'call-process
+      (apply #'call-process
              (append args (list "-o" folder) searchquery)))))
 
 (defun nnmairix-call-mairix-binary-raw (command query)
@@ -1272,7 +1272,7 @@ If THREADS is non-nil, enable full threads."
       (when (> (length command) 1)
         (setq args (append args (cdr command))))
       (setq args (append args '("-r")))
-      (apply 'call-process
+      (apply #'call-process
              (append args query)))))
 
 (defun nnmairix-get-server ()
@@ -1382,9 +1382,9 @@ This should correct problems of wrong article counts when using
 nnmairix with nnml backends."
   (let* ((files
          (sort
-          (mapcar 'string-to-number
+          (mapcar #'string-to-number
                   (directory-files path nil "[0-9]+" t))
-          '<))
+          #'<))
          (lastplusone (car files))
          (path (file-name-as-directory path)))
     (dolist (cur files)
@@ -1774,7 +1774,7 @@ If VERSION is a string: must be contained in mairix version output."
               (let* ((commandsplit (split-string nnmairix-mairix-command))
                      (args (append (list (car commandsplit))
                                    '(nil t nil) (cdr commandsplit) '("-V"))))
-              (apply 'call-process args)
+              (apply #'call-process args)
               (goto-char (point-min))
               (re-search-forward "mairix.*")
               (match-string 0))))
@@ -1920,7 +1920,7 @@ If WITHVALUES is t, query is based on current article."
       (when (not (zerop (length flag)))
         (push (concat "F:" flag) query)))
     ;; return query string
-    (mapconcat 'identity query " ")))
+    (mapconcat #'identity query " ")))
 
 
 (defun nnmairix-widget-create-query (&optional values)
@@ -1997,7 +1997,7 @@ VALUES may contain values for editable fields from current article."
   "Add a widget NAME with optional ARGS."
   (push
    (list name
-         (apply 'widget-create args))
+         (apply #'widget-create args))
    nnmairix-widgets))
 
 (defun nnmairix-widget-toggle-activate (widget)
diff --git a/lisp/gnus/nnmh.el b/lisp/gnus/nnmh.el
index 82ed091982e..46abf46ce75 100644
--- a/lisp/gnus/nnmh.el
+++ b/lisp/gnus/nnmh.el
@@ -171,9 +171,9 @@ as unread by Gnus.")
         (nnheader-re-read-dir pathname)
         (setq dir
               (sort
-               (mapcar 'string-to-number
+               (mapcar #'string-to-number
                        (directory-files pathname nil "\\`[0-9]+\\'" t))
-               '<))
+               #'<))
         (cond
          (dir
           (setq nnmh-group-alist
@@ -358,12 +358,12 @@ as unread by Gnus.")
             nnmh-group-alist)
       (nnmh-possibly-create-directory group)
       (nnmh-possibly-change-directory group server)
-      (let ((articles (mapcar 'string-to-number
+      (let ((articles (mapcar #'string-to-number
                               (directory-files
                                nnmh-current-directory nil "\\`[0-9]+\\'"))))
         (when articles
-          (setcar active (apply 'min articles))
-          (setcdr active (apply 'max articles))))))
+          (setcar active (apply #'min articles))
+          (setcdr active (apply #'max articles))))))
   t)
 
 (deffoo nnmh-request-delete-group (group &optional force server)
@@ -484,9 +484,9 @@ as unread by Gnus.")
         (gnus-make-directory dir))
       ;; Find the highest number in the group.
       (let ((files (sort
-                    (mapcar 'string-to-number
+                    (mapcar #'string-to-number
                             (directory-files dir nil "\\`[0-9]+\\'"))
-                    '>)))
+                    #'>)))
         (when files
           (setcdr active (car files)))))
     (setcdr active (1+ (cdr active)))
@@ -507,10 +507,10 @@ as unread by Gnus.")
   ;; articles in this folder.  The articles that are "new" will be
   ;; marked as unread by Gnus.
   (let* ((dir nnmh-current-directory)
-         (files (sort (mapcar 'string-to-number
+         (files (sort (mapcar #'string-to-number
                               (directory-files nnmh-current-directory
                                                nil "\\`[0-9]+\\'" t))
-                      '<))
+                      #'<))
          (nnmh-file (concat dir ".nnmh-articles"))
          new articles)
     ;; Load the .nnmh-articles file.
@@ -557,7 +557,7 @@ as unread by Gnus.")
     (when new
       (gnus-make-articles-unread
        (gnus-group-prefixed-name group (list 'nnmh ""))
-       (setq new (sort new '<))))
+       (setq new (sort new #'<))))
     ;; Sort the article list with highest numbers first.
     (setq articles (sort articles (lambda (art1 art2)
                                     (> (car art1) (car art2)))))
diff --git a/lisp/gnus/nnml.el b/lisp/gnus/nnml.el
index 3cdfc749703..eaa2004272f 100644
--- a/lisp/gnus/nnml.el
+++ b/lisp/gnus/nnml.el
@@ -278,8 +278,8 @@ non-nil.")
       (let* ((file-name-coding-system nnmail-pathname-coding-system)
              (articles (nnml-directory-articles nnml-current-directory)))
         (when articles
-          (setcar active (apply 'min articles))
-          (setcdr active (apply 'max articles))))
+          (setcar active (apply #'min articles))
+          (setcdr active (apply #'max articles))))
       (nnmail-save-active nnml-group-alist nnml-active-file)
       t))))
 
@@ -307,7 +307,7 @@ non-nil.")
          article rest mod-time number target)
     (nnmail-activate 'nnml)
 
-    (setq active-articles (sort active-articles '<))
+    (setq active-articles (sort active-articles #'<))
     ;; Articles not listed in active-articles are already gone,
     ;; so don't try to expire them.
     (setq articles (gnus-sorted-intersection articles active-articles))
@@ -353,7 +353,7 @@ non-nil.")
     (let ((active (nth 1 (assoc-string group nnml-group-alist))))
       (when active
         (setcar active (or (and active-articles
-                                (apply 'min active-articles))
+                                (apply #'min active-articles))
                            (1+ (cdr active)))))
       (nnmail-save-active nnml-group-alist nnml-active-file))
     (nnml-save-nov)
@@ -705,7 +705,7 @@ article number.  This function is called narrowed to an article."
         (setq nnml-article-file-alist
               (sort
                (nnml-current-group-article-to-file-alist)
-               'car-less-than-car)))
+               #'car-less-than-car)))
       (setq active
             (if nnml-article-file-alist
                 (cons (caar nnml-article-file-alist)
@@ -856,7 +856,7 @@ Unless no-active is non-nil, update the active file too."
           (nnml-generate-nov-databases-directory dir seen)))
       ;; Do this directory.
       (let ((nnml-files (sort (nnheader-article-to-file-alist dir)
-                         'car-less-than-car)))
+                              #'car-less-than-car)))
         (if (not nnml-files)
             (let* ((group (nnheader-file-to-group
                            (directory-file-name dir) nnml-directory))
@@ -1010,7 +1010,7 @@ Use the nov database for the current group if available."
   (unless nnml-article-file-alist
     (setq nnml-article-file-alist
           (sort (nnml-current-group-article-to-file-alist)
-                'car-less-than-car)))
+                #'car-less-than-car)))
   (if (not nnml-article-file-alist)
       ;; The group is empty: do nothing but return t
       t
diff --git a/lisp/gnus/nnrss.el b/lisp/gnus/nnrss.el
index f9e0a08a06e..a340c9e2b8f 100644
--- a/lisp/gnus/nnrss.el
+++ b/lisp/gnus/nnrss.el
@@ -798,7 +798,7 @@ It is useful when `(setq nnrss-use-local t)'."
 
 (defun nnrss-node-just-text (node)
   (if (and node (listp node))
-      (mapconcat 'nnrss-node-just-text (cddr node) " ")
+      (mapconcat #'nnrss-node-just-text (cddr node) " ")
     node))
 
 (defun nnrss-find-el (tag data &optional found-list)
diff --git a/lisp/gnus/nnselect.el b/lisp/gnus/nnselect.el
index ba0e60a2673..fffa2d27312 100644
--- a/lisp/gnus/nnselect.el
+++ b/lisp/gnus/nnselect.el
@@ -81,12 +81,12 @@
   "Compress ARTLIST."
   (let (selection)
     (pcase-dolist (`(,artgroup . ,arts)
-                   (nnselect-categorize artlist 'nnselect-artitem-group))
+                   (nnselect-categorize artlist #'nnselect-artitem-group))
       (let (list)
         (pcase-dolist (`(,rsv . ,articles)
                        (nnselect-categorize
-                        arts 'nnselect-artitem-rsv 'nnselect-artitem-number))
-          (push (cons rsv (gnus-compress-sequence (sort articles '<)))
+                        arts #'nnselect-artitem-rsv #'nnselect-artitem-number))
+          (push (cons rsv (gnus-compress-sequence (sort articles #'<)))
                 list))
         (push (cons artgroup list) selection)))
     selection))
@@ -200,25 +200,27 @@ as `(keyfunc member)' and the corresponding element is just
 
 (define-inline ids-by-group (articles)
   (inline-quote
-   (nnselect-categorize ,articles 'nnselect-article-group
-                        'nnselect-article-id)))
+   (nnselect-categorize ,articles #'nnselect-article-group
+                        #'nnselect-article-id)))
 
 (define-inline numbers-by-group (articles &optional type)
   (inline-quote
    (cond
     ((eq ,type 'range)
      (nnselect-categorize (gnus-uncompress-range ,articles)
-                          'nnselect-article-group 'nnselect-article-number))
+                          #'nnselect-article-group #'nnselect-article-number))
     ((eq ,type 'tuple)
      (nnselect-categorize ,articles
                           #'(lambda (elem)
                               (nnselect-article-group (car elem)))
                           #'(lambda (elem)
                               (cons (nnselect-article-number
-                                     (car elem)) (cdr elem)))))
+                                     (car elem))
+                                    (cdr elem)))))
     (t
      (nnselect-categorize ,articles
-                          'nnselect-article-group 'nnselect-article-number)))))
+                          #'nnselect-article-group
+                          #'nnselect-article-number)))))
 
 (defmacro nnselect-add-prefix (group)
   "Ensures that the GROUP has an nnselect prefix."
@@ -319,7 +321,7 @@ If this variable is nil, or if the provided function returns nil,
             headers)
         (with-current-buffer nntp-server-buffer
           (pcase-dolist (`(,artgroup . ,artids) gartids)
-            (let ((artlist (sort (mapcar 'cdr artids) '<))
+            (let ((artlist (sort (mapcar #'cdr artids) #'<))
                   (gnus-override-method (gnus-find-method-for-group artgroup))
                   (fetch-old
                    (or
@@ -385,7 +387,8 @@ If this variable is nil, or if the provided function returns nil,
                       (list
                        (gnus-method-to-server
                         (gnus-find-method-for-group
-                         (nnselect-article-group x)))) servers :test 'equal)))
+                         (nnselect-article-group x))))
+                      servers :test 'equal)))
                  (gnus-articles-in-thread thread)))))
         (setq servers (list (list server))))
       (setq artlist
@@ -455,7 +458,7 @@ If this variable is nil, or if the provided function returns nil,
   (if force
       (let (not-expired)
         (pcase-dolist (`(,artgroup . ,artids) (ids-by-group articles))
-          (let ((artlist (sort (mapcar 'cdr artids) '<)))
+          (let ((artlist (sort (mapcar #'cdr artids) #'<)))
             (unless (gnus-check-backend-function 'request-expire-articles
                                                  artgroup)
               (error "Group %s does not support article expiration" artgroup))
@@ -467,7 +470,7 @@ If this variable is nil, or if the provided function returns nil,
                             (gnus-request-expire-articles
                              artlist artgroup force)))
                   not-expired)))
-        (sort (delq nil not-expired) '<))
+        (sort (delq nil not-expired) #'<))
     articles))
 
 
@@ -518,11 +521,11 @@ If this variable is nil, or if the provided function returns nil,
          (mapcar
           (lambda (artgroup)
             (list (car artgroup)
-                  (gnus-compress-sequence (sort (cdr artgroup) '<))
+                  (gnus-compress-sequence (sort (cdr artgroup) #'<))
                   action marks))
           (numbers-by-group range 'range))))
      actions)
-    'car 'cdr)))
+    #'car #'cdr)))
 
 (deffoo nnselect-request-update-info (group info &optional _server)
   (let* ((group (nnselect-add-prefix group))
@@ -651,8 +654,9 @@ If this variable is nil, or if the provided function returns nil,
              new-nnselect-artlist)
             (setq headers
                   (gnus-fetch-headers
-                   (append (sort old-arts '<)
-                           (number-sequence first last)) nil t))
+                   (append (sort old-arts #'<)
+                           (number-sequence first last))
+                   nil t))
             (gnus-group-set-parameter
              group
              'nnselect-artlist
@@ -942,7 +946,7 @@ article came from is also searched."
                (gnus-remove-from-range
                 old-unread
                 (cdr (assoc artgroup select-reads)))
-               (sort (cdr (assoc artgroup select-unreads)) '<))))
+               (sort (cdr (assoc artgroup select-unreads)) #'<))))
             (gnus-get-unread-articles-in-group
              group-info (gnus-active artgroup) t)
             (gnus-group-update-group artgroup t t)))))))
diff --git a/lisp/gnus/nnspool.el b/lisp/gnus/nnspool.el
index 9de59d8631d..cb854178564 100644
--- a/lisp/gnus/nnspool.el
+++ b/lisp/gnus/nnspool.el
@@ -261,7 +261,7 @@ there.")
         ;; Yes, completely empty spool directories *are* possible.
         ;; Fix by Sudish Joseph <joseph@cis.ohio-state.edu>
         (when (setq dir (directory-files pathname nil "\\`[0-9]+\\'" t))
-          (setq dir (sort (mapcar 'string-to-number dir) '<)))
+          (setq dir (sort (mapcar #'string-to-number dir) #'<)))
         (if dir
             (nnheader-insert
              "211 %d %d %d %s\n" (length dir) (car dir)
@@ -331,7 +331,7 @@ there.")
            (buf (current-buffer))
            (proc
             (condition-case err
-                (apply 'start-process "*nnspool inews*" inews-buffer
+                (apply #'start-process "*nnspool inews*" inews-buffer
                        nnspool-inews-program nnspool-inews-switches)
               (error
                (nnheader-report 'nnspool "inews error: %S" err)))))
@@ -409,7 +409,7 @@ there.")
                                 (<= last (car arts)))
                       (pop arts))
                     ;; The articles in `arts' are missing from the buffer.
-                    (mapc 'nnspool-insert-nov-head arts)
+                    (mapc #'nnspool-insert-nov-head arts)
                     t))))))))))
 
 (defun nnspool-insert-nov-head (article)
diff --git a/lisp/gnus/nnvirtual.el b/lisp/gnus/nnvirtual.el
index 1e2feda6365..902df868f80 100644
--- a/lisp/gnus/nnvirtual.el
+++ b/lisp/gnus/nnvirtual.el
@@ -367,7 +367,7 @@ It is computed from the marks of individual component groups.")
                                    group article))
                               (gnus-uncompress-range
                                (gnus-group-expire-articles-1 group))))))
-    (sort (delq nil unexpired) '<)))
+    (sort (delq nil unexpired) #'<)))
 
 
 ;;; Internal functions.
@@ -378,7 +378,7 @@ It is computed from the marks of individual component groups.")
     (let* ((dependencies (make-hash-table :test #'equal))
            (headers (gnus-get-newsgroup-headers dependencies)))
       (erase-buffer)
-      (mapc 'nnheader-insert-nov headers))))
+      (mapc #'nnheader-insert-nov headers))))
 
 
 (defun nnvirtual-update-xref-header (group article prefix sysname)
@@ -502,7 +502,7 @@ If UPDATE-P is not nil, call gnus-group-update-group on the components."
   "Merge many sorted lists of numbers."
   (if (null (cdr lists))
       (car lists)
-    (sort (apply 'nconc lists) '<)))
+    (sort (apply #'nconc lists) #'<)))
 
 
 ;; We map between virtual articles and real articles in a manner
@@ -648,7 +648,7 @@ numbers has no corresponding component article, then it is left out of
 the result."
   (when (numberp (cdr-safe articles))
     (setq articles (list articles)))
-  (let ((carticles (mapcar 'list nnvirtual-component-groups))
+  (let ((carticles (mapcar #'list nnvirtual-component-groups))
         a i j article entry)
     (while (setq a (pop articles))
       (if (atom a)
@@ -750,7 +750,7 @@ based on the marks on the component groups."
     ;; Now that the mapping tables are generated, we can convert
     ;; and combine the separate component unreads and marks lists
     ;; into single lists of virtual article numbers.
-    (setq unreads (apply 'nnvirtual-merge-sorted-lists
+    (setq unreads (apply #'nnvirtual-merge-sorted-lists
                          (mapcar (lambda (x)
                                    (nnvirtual-reverse-map-sequence
                                     (car x) (cdr x)))
@@ -760,7 +760,7 @@ based on the marks on the component groups."
                    (cons (cdr type)
                          (gnus-compress-sequence
                           (apply
-                           'nnvirtual-merge-sorted-lists
+                           #'nnvirtual-merge-sorted-lists
                            (mapcar (lambda (x)
                                      (nnvirtual-reverse-map-sequence
                                       (car x)
diff --git a/lisp/gnus/nnweb.el b/lisp/gnus/nnweb.el
index b8fb4a8373a..2a948254717 100644
--- a/lisp/gnus/nnweb.el
+++ b/lisp/gnus/nnweb.el
@@ -411,7 +411,7 @@ Valid types include `google', `dejanews', and `gmane'.")
           ;; Return the articles in the right order.
           (nnheader-message 7 "Searching google...done")
           (setq nnweb-articles
-                (sort nnweb-articles 'car-less-than-car))))))
+                (sort nnweb-articles #'car-less-than-car))))))
 
 (defun nnweb-google-search (search)
   (mm-url-insert
@@ -481,7 +481,7 @@ Valid types include `google', `dejanews', and `gmane'.")
           (forward-line 1)))
       (nnheader-message 7 "Searching Gmane...done")
       (setq nnweb-articles
-            (sort (nconc nnweb-articles map) 'car-less-than-car)))))
+            (sort (nconc nnweb-articles map) #'car-less-than-car)))))
 
 (defun nnweb-gmane-wash-article ()
   (let ((case-fold-search t))
@@ -534,7 +534,7 @@ Valid types include `google', `dejanews', and `gmane'.")
              (nth 1 parse)
              " "))
     (insert ">\n")
-    (mapc 'nnweb-insert-html (nth 2 parse))
+    (mapc #'nnweb-insert-html (nth 2 parse))
     (insert "</" (symbol-name (car parse)) ">\n")))
 
 (defun nnweb-parse-find (type parse &optional maxdepth)
diff --git a/lisp/gnus/smiley.el b/lisp/gnus/smiley.el
index d9e04f3b40c..9884bcc0752 100644
--- a/lisp/gnus/smiley.el
+++ b/lisp/gnus/smiley.el
@@ -71,9 +71,8 @@
          (set-default symbol value)
          (setq smiley-data-directory (smiley-directory))
          (smiley-update-cache))
-  :initialize 'custom-initialize-default
-  :version "23.1" ;; No Gnus
-  :group 'smiley)
+  :initialize #'custom-initialize-default
+  :version "23.1") ;; No Gnus
 
 ;; For compatibility, honor the variable `smiley-data-directory' if the user
 ;; has set it.
@@ -94,9 +93,8 @@ is nil, use `smiley-style'."
   :set (lambda (symbol value)
          (set-default symbol value)
          (smiley-update-cache))
-  :initialize 'custom-initialize-default
-  :type 'directory
-  :group 'smiley)
+  :initialize #'custom-initialize-default
+  :type 'directory)
 
 (defcustom smiley-emoji-regexp-alist
   '(("\\(;-)\\)\\W" 1 "😉")
@@ -124,8 +122,7 @@ regexp to replace with EMOJI."
   :set (lambda (symbol value)
          (set-default symbol value)
          (smiley-update-cache))
-  :initialize 'custom-initialize-default
-  :group 'smiley)
+  :initialize #'custom-initialize-default)
 
 ;; The XEmacs version has a baroque, if not rococo, set of these.
 (defcustom smiley-regexp-alist
@@ -154,8 +151,7 @@ regexp to replace with IMAGE.  IMAGE is the name of an image file in
   :set (lambda (symbol value)
          (set-default symbol value)
          (smiley-update-cache))
-  :initialize 'custom-initialize-default
-  :group 'smiley)
+  :initialize #'custom-initialize-default)
 
 (defcustom gnus-smiley-file-types
   (let ((types (list "pbm")))
@@ -166,8 +162,7 @@ regexp to replace with IMAGE.  IMAGE is the name of an image file in
     types)
   "List of suffixes on smiley file names to try."
   :version "24.1"
-  :type '(repeat string)
-  :group 'smiley)
+  :type '(repeat string))
 
 (defvar smiley-cached-regexp-alist nil)
 
diff --git a/lisp/gnus/smime.el b/lisp/gnus/smime.el
index ae5d171d871..147c51d89a6 100644
--- a/lisp/gnus/smime.el
+++ b/lisp/gnus/smime.el
@@ -282,7 +282,7 @@ key and certificate itself."
         (setenv "GNUS_SMIME_PASSPHRASE" passphrase))
     (prog1
         (when (prog1
-                  (apply 'smime-call-openssl-region b e (list buffer tmpfile)
+                  (apply #'smime-call-openssl-region b e (list buffer tmpfile)
                          "smime" "-sign" "-signer" (expand-file-name keyfile)
                          (append
                           (smime-make-certfiles certfiles)
@@ -314,9 +314,9 @@ is expected to contain of a PEM encoded certificate."
         (tmpfile (make-temp-file "smime")))
     (prog1
         (when (prog1
-                  (apply 'smime-call-openssl-region b e (list buffer tmpfile)
+                  (apply #'smime-call-openssl-region b e (list buffer tmpfile)
                          "smime" "-encrypt" smime-encrypt-cipher
-                         (mapcar 'expand-file-name certfiles))
+                         (mapcar #'expand-file-name certfiles))
                 (with-current-buffer smime-details-buffer
                   (insert-file-contents tmpfile)
                   (delete-file tmpfile)))
@@ -384,7 +384,7 @@ Any details (stdout and stderr) are left in the buffer specified by
     (with-temp-buffer
       (let ((result-buffer (current-buffer)))
         (with-current-buffer input-buffer
-          (if (apply 'smime-call-openssl-region b e (list result-buffer
+          (if (apply #'smime-call-openssl-region b e (list result-buffer
                                                           smime-details-buffer)
                      "smime" "-verify" "-out" "-" CAs)
               (with-current-buffer result-buffer
@@ -397,7 +397,7 @@ Returns non-nil on success.
 Any details (stdout and stderr) are left in the buffer specified by
 `smime-details-buffer'."
   (smime-new-details-buffer)
-  (if (apply 'smime-call-openssl-region b e (list smime-details-buffer t)
+  (if (apply #'smime-call-openssl-region b e (list smime-details-buffer t)
              "smime" "-verify" "-noverify" "-out" `(,null-device))
       t
     (insert-buffer-substring smime-details-buffer)
@@ -416,7 +416,7 @@ in the buffer specified by `smime-details-buffer'."
     (if passphrase
         (setenv "GNUS_SMIME_PASSPHRASE" passphrase))
     (if (prog1
-            (apply 'smime-call-openssl-region b e
+            (apply #'smime-call-openssl-region b e
                    (list buffer tmpfile)
                    "smime" "-decrypt" "-recip" (expand-file-name keyfile)
                    (if passphrase
diff --git a/lisp/gnus/spam-report.el b/lisp/gnus/spam-report.el
index 8c148ce9d91..e2125563f2a 100644
--- a/lisp/gnus/spam-report.el
+++ b/lisp/gnus/spam-report.el
@@ -345,8 +345,8 @@ Spam reports will be queued with \\[spam-report-url-to-file] when
 the Agent is unplugged, and will be submitted in a batch when the
 Agent is plugged."
   (interactive)
-  (add-hook 'gnus-agent-plugged-hook 'spam-report-plug-agent)
-  (add-hook 'gnus-agent-unplugged-hook 'spam-report-unplug-agent))
+  (add-hook 'gnus-agent-plugged-hook #'spam-report-plug-agent)
+  (add-hook 'gnus-agent-unplugged-hook #'spam-report-unplug-agent))
 
 ;;;###autoload
 (defun spam-report-deagentize ()
@@ -354,8 +354,8 @@ Agent is plugged."
 Spam reports will be queued with the method used when
 \\[spam-report-agentize] was run."
   (interactive)
-  (remove-hook 'gnus-agent-plugged-hook 'spam-report-plug-agent)
-  (remove-hook 'gnus-agent-unplugged-hook 'spam-report-unplug-agent))
+  (remove-hook 'gnus-agent-plugged-hook #'spam-report-plug-agent)
+  (remove-hook 'gnus-agent-unplugged-hook #'spam-report-unplug-agent))
 
 (defun spam-report-plug-agent ()
   "Adjust spam report settings for plugged state.
diff --git a/lisp/gnus/spam-stat.el b/lisp/gnus/spam-stat.el
index 3662ade2663..89c2deb36f0 100644
--- a/lisp/gnus/spam-stat.el
+++ b/lisp/gnus/spam-stat.el
@@ -501,7 +501,7 @@ where DIFF is the difference between SCORE and 0.5."
 Add user supplied modifications if supplied."
   (interactive) ; helps in debugging.
   (setq spam-stat-score-data (spam-stat-buffer-words-with-scores))
-  (let* ((probs (mapcar 'cadr spam-stat-score-data))
+  (let* ((probs (mapcar #'cadr spam-stat-score-data))
          (prod (apply #'* probs))
          (score0
           (/ prod (+ prod (apply #'* (mapcar #'(lambda (x) (- 1 x))
@@ -652,19 +652,19 @@ COUNT defaults to 5"
   "Install the spam-stat function hooks."
   (interactive)
   (add-hook 'nnmail-prepare-incoming-message-hook
-            'spam-stat-store-current-buffer)
+            #'spam-stat-store-current-buffer)
   (add-hook 'gnus-select-article-hook
-            'spam-stat-store-gnus-article-buffer))
+            #'spam-stat-store-gnus-article-buffer))
 
 (defun spam-stat-unload-hook ()
   "Uninstall the spam-stat function hooks."
   (interactive)
   (remove-hook 'nnmail-prepare-incoming-message-hook
-               'spam-stat-store-current-buffer)
+               #'spam-stat-store-current-buffer)
   (remove-hook 'gnus-select-article-hook
-               'spam-stat-store-gnus-article-buffer))
+               #'spam-stat-store-gnus-article-buffer))
 
-(add-hook 'spam-stat-unload-hook 'spam-stat-unload-hook)
+(add-hook 'spam-stat-unload-hook #'spam-stat-unload-hook)
 
 (provide 'spam-stat)
 
diff --git a/lisp/gnus/spam-wash.el b/lisp/gnus/spam-wash.el
index 1d00a39060d..1c755fb464e 100644
--- a/lisp/gnus/spam-wash.el
+++ b/lisp/gnus/spam-wash.el
@@ -57,7 +57,7 @@
 
 (defun spam-treat-parts (handle)
   (if (stringp (car handle))
-      (mapcar 'spam-treat-parts (cdr handle))
+      (mapcar #'spam-treat-parts (cdr handle))
     (if (bufferp (car handle))
         (save-restriction
           (narrow-to-region (point) (point))
@@ -65,7 +65,7 @@
                 (string-match "text" (car (mm-handle-type handle))))
           (mm-insert-part handle))
           (goto-char (point-max)))
-      (mapcar 'spam-treat-parts handle))))
+      (mapcar #'spam-treat-parts handle))))
 
 (provide 'spam-wash)
 
diff --git a/lisp/gnus/spam.el b/lisp/gnus/spam.el
index 22810332b65..3f4fd3614ee 100644
--- a/lisp/gnus/spam.el
+++ b/lisp/gnus/spam.el
@@ -705,7 +705,7 @@ finds ham or spam.")
   "Clear the `spam-caches' entry for a check."
   (remhash symbol spam-caches))
 
-(define-obsolete-function-alias 'spam-xor 'xor "27.1")
+(define-obsolete-function-alias 'spam-xor #'xor "27.1")
 
 (defun spam-set-difference (list1 list2)
   "Return a set difference of LIST1 and LIST2.
@@ -727,7 +727,7 @@ When either list is nil, the other is returned."
     (let* ((marks (spam-group-ham-marks group spam))
            (marks (if (symbolp mark)
                       marks
-                    (mapcar 'symbol-value marks))))
+                    (mapcar #'symbol-value marks))))
       (memq mark marks))))
 
 (defun spam-group-spam-mark-p (group mark)
@@ -1014,28 +1014,28 @@ backends)."
 
 ;;{{{ backend installations
 (spam-install-checkonly-backend 'spam-use-blackholes
-                                'spam-check-blackholes)
+                                #'spam-check-blackholes)
 
 (spam-install-checkonly-backend 'spam-use-hashcash
-                                'spam-check-hashcash)
+                                #'spam-check-hashcash)
 
 (spam-install-checkonly-backend 'spam-use-spamassassin-headers
-                                'spam-check-spamassassin-headers)
+                                #'spam-check-spamassassin-headers)
 
 (spam-install-checkonly-backend 'spam-use-bogofilter-headers
-                                'spam-check-bogofilter-headers)
+                                #'spam-check-bogofilter-headers)
 
 (spam-install-checkonly-backend 'spam-use-bsfilter-headers
-                                'spam-check-bsfilter-headers)
+                                #'spam-check-bsfilter-headers)
 
 (spam-install-checkonly-backend 'spam-use-gmane-xref
-                                'spam-check-gmane-xref)
+                                #'spam-check-gmane-xref)
 
 (spam-install-checkonly-backend 'spam-use-regex-headers
-                                'spam-check-regex-headers)
+                                #'spam-check-regex-headers)
 
 (spam-install-statistical-checkonly-backend 'spam-use-regex-body
-                                            'spam-check-regex-body)
+                                            #'spam-check-regex-body)
 
 ;; TODO: NOTE: spam-use-ham-copy is now obsolete, use (ham spam-use-copy)
 (spam-install-mover-backend 'spam-use-move
@@ -1045,94 +1045,94 @@ backends)."
                             nil)
 
 (spam-install-nocheck-backend 'spam-use-copy
-                              'spam-copy-ham-routine
-                              'spam-copy-spam-routine
+                              #'spam-copy-ham-routine
+                              #'spam-copy-spam-routine
                               nil
                               nil)
 
 (spam-install-nocheck-backend 'spam-use-gmane
-                              'spam-report-gmane-unregister-routine
-                              'spam-report-gmane-register-routine
-                              'spam-report-gmane-register-routine
-                              'spam-report-gmane-unregister-routine)
+                              #'spam-report-gmane-unregister-routine
+                              #'spam-report-gmane-register-routine
+                              #'spam-report-gmane-register-routine
+                              #'spam-report-gmane-unregister-routine)
 
 (spam-install-nocheck-backend 'spam-use-resend
-                              'spam-report-resend-register-ham-routine
-                              'spam-report-resend-register-routine
+                              #'spam-report-resend-register-ham-routine
+                              #'spam-report-resend-register-routine
                               nil
                               nil)
 
 (spam-install-backend 'spam-use-BBDB
-                      'spam-check-BBDB
-                      'spam-BBDB-register-routine
+                      #'spam-check-BBDB
+                      #'spam-BBDB-register-routine
                       nil
-                      'spam-BBDB-unregister-routine
+                      #'spam-BBDB-unregister-routine
                       nil)
 
 (spam-install-backend-alias 'spam-use-BBDB 'spam-use-BBDB-exclusive)
 
 (spam-install-backend 'spam-use-blacklist
-                      'spam-check-blacklist
+                      #'spam-check-blacklist
                       nil
-                      'spam-blacklist-register-routine
+                      #'spam-blacklist-register-routine
                       nil
-                      'spam-blacklist-unregister-routine)
+                      #'spam-blacklist-unregister-routine)
 
 (spam-install-backend 'spam-use-whitelist
-                      'spam-check-whitelist
-                      'spam-whitelist-register-routine
+                      #'spam-check-whitelist
+                      #'spam-whitelist-register-routine
                       nil
-                      'spam-whitelist-unregister-routine
+                      #'spam-whitelist-unregister-routine
                       nil)
 
 (spam-install-statistical-backend 'spam-use-ifile
-                                  'spam-check-ifile
-                                  'spam-ifile-register-ham-routine
-                                  'spam-ifile-register-spam-routine
-                                  'spam-ifile-unregister-ham-routine
-                                  'spam-ifile-unregister-spam-routine)
+                                  #'spam-check-ifile
+                                  #'spam-ifile-register-ham-routine
+                                  #'spam-ifile-register-spam-routine
+                                  #'spam-ifile-unregister-ham-routine
+                                  #'spam-ifile-unregister-spam-routine)
 
 (spam-install-statistical-backend 'spam-use-spamoracle
-                                  'spam-check-spamoracle
-                                  'spam-spamoracle-learn-ham
-                                  'spam-spamoracle-learn-spam
-                                  'spam-spamoracle-unlearn-ham
-                                  'spam-spamoracle-unlearn-spam)
+                                  #'spam-check-spamoracle
+                                  #'spam-spamoracle-learn-ham
+                                  #'spam-spamoracle-learn-spam
+                                  #'spam-spamoracle-unlearn-ham
+                                  #'spam-spamoracle-unlearn-spam)
 
 (spam-install-statistical-backend 'spam-use-stat
-                                  'spam-check-stat
-                                  'spam-stat-register-ham-routine
-                                  'spam-stat-register-spam-routine
-                                  'spam-stat-unregister-ham-routine
-                                  'spam-stat-unregister-spam-routine)
+                                  #'spam-check-stat
+                                  #'spam-stat-register-ham-routine
+                                  #'spam-stat-register-spam-routine
+                                  #'spam-stat-unregister-ham-routine
+                                  #'spam-stat-unregister-spam-routine)
 
 (spam-install-statistical-backend 'spam-use-spamassassin
-                                  'spam-check-spamassassin
-                                  'spam-spamassassin-register-ham-routine
-                                  'spam-spamassassin-register-spam-routine
-                                  'spam-spamassassin-unregister-ham-routine
-                                  'spam-spamassassin-unregister-spam-routine)
+                                  #'spam-check-spamassassin
+                                  #'spam-spamassassin-register-ham-routine
+                                  #'spam-spamassassin-register-spam-routine
+                                  #'spam-spamassassin-unregister-ham-routine
+                                  #'spam-spamassassin-unregister-spam-routine)
 
 (spam-install-statistical-backend 'spam-use-bogofilter
-                                  'spam-check-bogofilter
-                                  'spam-bogofilter-register-ham-routine
-                                  'spam-bogofilter-register-spam-routine
-                                  'spam-bogofilter-unregister-ham-routine
-                                  'spam-bogofilter-unregister-spam-routine)
+                                  #'spam-check-bogofilter
+                                  #'spam-bogofilter-register-ham-routine
+                                  #'spam-bogofilter-register-spam-routine
+                                  #'spam-bogofilter-unregister-ham-routine
+                                  #'spam-bogofilter-unregister-spam-routine)
 
 (spam-install-statistical-backend 'spam-use-bsfilter
-                                  'spam-check-bsfilter
-                                  'spam-bsfilter-register-ham-routine
-                                  'spam-bsfilter-register-spam-routine
-                                  'spam-bsfilter-unregister-ham-routine
-                                  'spam-bsfilter-unregister-spam-routine)
+                                  #'spam-check-bsfilter
+                                  #'spam-bsfilter-register-ham-routine
+                                  #'spam-bsfilter-register-spam-routine
+                                  #'spam-bsfilter-unregister-ham-routine
+                                  #'spam-bsfilter-unregister-spam-routine)
 
 (spam-install-statistical-backend 'spam-use-crm114
-                                  'spam-check-crm114
-                                  'spam-crm114-register-ham-routine
-                                  'spam-crm114-register-spam-routine
-                                  'spam-crm114-unregister-ham-routine
-                                  'spam-crm114-unregister-spam-routine)
+                                  #'spam-check-crm114
+                                  #'spam-crm114-register-ham-routine
+                                  #'spam-crm114-register-spam-routine
+                                  #'spam-crm114-unregister-ham-routine
+                                  #'spam-crm114-unregister-spam-routine)
 ;;}}}
 
 ;;{{{ scoring and summary formatting
@@ -1709,7 +1709,7 @@ See the Info node `(gnus)Fancy Mail Splitting' for more details."
                          (if (or (null first-method)
                                  (equal first-method 'default))
                              (spam-split)
-                           (apply 'spam-split methods))))))
+                           (apply #'spam-split methods))))))
              (if (equal split-return 'spam)
                  (gnus-summary-mark-article article gnus-spam-mark))
 
@@ -1981,7 +1981,7 @@ See the Info node `(gnus)Fancy Mail Splitting' for more details."
 
 (defun spam-reverse-ip-string (ip)
   (when (stringp ip)
-    (mapconcat 'identity
+    (mapconcat #'identity
                (nreverse (split-string ip "\\."))
                ".")))
 
@@ -2139,7 +2139,7 @@ See `spam-ifile-database'."
       (let ((temp-buffer-name (buffer-name))
             (db-param (spam-get-ifile-database-parameter)))
         (with-current-buffer article-buffer-name
-          (apply 'call-process-region
+          (apply #'call-process-region
                  (point-min) (point-max) spam-ifile-program
                  nil temp-buffer-name nil "-c"
                  (if db-param `(,db-param "-q") '("-q"))))
@@ -2167,7 +2167,7 @@ Uses `gnus-newsgroup-name' if category is nil (for ham registration)."
         (let ((article-string (spam-get-article-as-string article)))
           (when (stringp article-string)
             (insert article-string))))
-      (apply 'call-process-region
+      (apply #'call-process-region
              (point-min) (point-max) spam-ifile-program
              nil nil nil
              add-or-delete-option category
@@ -2406,11 +2406,11 @@ With a non-nil REMOVE, remove the ADDRESSES."
 ;;{{{ Spam-report glue (gmane and resend reporting)
 (defun spam-report-gmane-register-routine (articles)
   (when articles
-    (apply 'spam-report-gmane-spam articles)))
+    (apply #'spam-report-gmane-spam articles)))
 
 (defun spam-report-gmane-unregister-routine (articles)
   (when articles
-    (apply 'spam-report-gmane-ham articles)))
+    (apply #'spam-report-gmane-ham articles)))
 
 (defun spam-report-resend-register-ham-routine (articles)
   (spam-report-resend-register-routine articles t))
@@ -2474,7 +2474,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
         (with-temp-buffer
           (let ((temp-buffer-name (buffer-name)))
             (with-current-buffer article-buffer-name
-              (apply 'call-process-region
+              (apply #'call-process-region
                      (point-min) (point-max)
                      spam-bogofilter-program
                      nil temp-buffer-name nil
@@ -2502,7 +2502,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
             (with-temp-buffer
               (insert article-string)
 
-              (apply 'call-process-region
+              (apply #'call-process-region
                      (point-min) (point-max)
                      spam-bogofilter-program
                      nil nil nil switch
@@ -2532,7 +2532,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
       (let ((temp-buffer-name (buffer-name)))
         (with-current-buffer article-buffer-name
           (let ((status
-                 (apply 'call-process-region
+                 (apply #'call-process-region
                         (point-min) (point-max)
                         spam-spamoracle-binary
                         nil temp-buffer-name nil
@@ -2559,7 +2559,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
                         "-spam"
                       "-good"))
                (status
-                (apply 'call-process-region
+                (apply #'call-process-region
                        (point-min) (point-max)
                        spam-spamoracle-binary
                        nil temp-buffer-name nil
@@ -2607,7 +2607,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
     (with-temp-buffer
       (let ((temp-buffer-name (buffer-name)))
         (with-current-buffer article-buffer-name
-          (apply 'call-process-region
+          (apply #'call-process-region
                  (point-min) (point-max) spam-assassin-program
                  nil temp-buffer-name nil spam-spamassassin-arguments))
         ;; check the return now (we're back in the temp buffer)
@@ -2648,7 +2648,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
                 (insert article-string)
                 (insert "\n"))))
           ;; call sa-learn on all messages at the same time
-          (apply 'call-process-region
+          (apply #'call-process-region
                  (point-min) (point-max)
                  spam-sa-learn-program
                  nil nil nil "--mbox"
@@ -2703,7 +2703,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
     (with-temp-buffer
       (let ((temp-buffer-name (buffer-name)))
         (with-current-buffer article-buffer-name
-          (apply 'call-process-region
+          (apply #'call-process-region
                  (point-min) (point-max)
                  spam-bsfilter-program
                  nil temp-buffer-name nil
@@ -2731,7 +2731,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
       (when (stringp article-string)
         (with-temp-buffer
           (insert article-string)
-          (apply 'call-process-region
+          (apply #'call-process-region
                  (point-min) (point-max)
                  spam-bsfilter-program
                  nil nil nil switch
@@ -2788,7 +2788,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
     (with-temp-buffer
       (let ((temp-buffer-name (buffer-name)))
         (with-current-buffer article-buffer-name
-          (apply 'call-process-region
+          (apply #'call-process-region
                  (point-min) (point-max)
                  spam-crm114-program
                  nil temp-buffer-name nil
@@ -2814,7 +2814,7 @@ With a non-nil REMOVE, remove the ADDRESSES."
         (with-temp-buffer
           (insert article-string)
 
-          (apply 'call-process-region
+          (apply #'call-process-region
                  (point-min) (point-max)
                  spam-crm114-program
                  nil nil nil
@@ -2859,13 +2859,13 @@ installed through `spam-necessary-extra-headers'."
     (push '((eq mark gnus-spam-mark) . spam)
           gnus-summary-highlight)
     ;; Add hooks for loading and saving the spam stats
-    (add-hook 'gnus-save-newsrc-hook 'spam-maybe-spam-stat-save)
-    (add-hook 'gnus-get-top-new-news-hook 'spam-maybe-spam-stat-load)
-    (add-hook 'gnus-startup-hook 'spam-maybe-spam-stat-load)
-    (add-hook 'gnus-summary-prepare-exit-hook 'spam-summary-prepare-exit)
-    (add-hook 'gnus-summary-prepare-hook 'spam-summary-prepare)
-    (add-hook 'gnus-get-new-news-hook 'spam-setup-widening)
-    (add-hook 'gnus-summary-prepared-hook 'spam-find-spam)
+    (add-hook 'gnus-save-newsrc-hook #'spam-maybe-spam-stat-save)
+    (add-hook 'gnus-get-top-new-news-hook #'spam-maybe-spam-stat-load)
+    (add-hook 'gnus-startup-hook #'spam-maybe-spam-stat-load)
+    (add-hook 'gnus-summary-prepare-exit-hook #'spam-summary-prepare-exit)
+    (add-hook 'gnus-summary-prepare-hook #'spam-summary-prepare)
+    (add-hook 'gnus-get-new-news-hook #'spam-setup-widening)
+    (add-hook 'gnus-summary-prepared-hook #'spam-find-spam)
     ;; Don't install things more than once.
     (setq spam-install-hooks nil)))
 
@@ -2873,15 +2873,15 @@ installed through `spam-necessary-extra-headers'."
   "Uninstall the spam.el hooks."
   (interactive)
   (spam-teardown-widening)
-  (remove-hook 'gnus-save-newsrc-hook 'spam-maybe-spam-stat-save)
-  (remove-hook 'gnus-get-top-new-news-hook 'spam-maybe-spam-stat-load)
-  (remove-hook 'gnus-startup-hook 'spam-maybe-spam-stat-load)
-  (remove-hook 'gnus-summary-prepare-exit-hook 'spam-summary-prepare-exit)
-  (remove-hook 'gnus-summary-prepare-hook 'spam-summary-prepare)
-  (remove-hook 'gnus-get-new-news-hook 'spam-setup-widening)
-  (remove-hook 'gnus-summary-prepare-hook 'spam-find-spam))
-
-(add-hook 'spam-unload-hook 'spam-unload-hook)
+  (remove-hook 'gnus-save-newsrc-hook #'spam-maybe-spam-stat-save)
+  (remove-hook 'gnus-get-top-new-news-hook #'spam-maybe-spam-stat-load)
+  (remove-hook 'gnus-startup-hook #'spam-maybe-spam-stat-load)
+  (remove-hook 'gnus-summary-prepare-exit-hook #'spam-summary-prepare-exit)
+  (remove-hook 'gnus-summary-prepare-hook #'spam-summary-prepare)
+  (remove-hook 'gnus-get-new-news-hook #'spam-setup-widening)
+  (remove-hook 'gnus-summary-prepare-hook #'spam-find-spam))
+
+(add-hook 'spam-unload-hook #'spam-unload-hook)
 
 ;;}}}