(customize-changed-options): New function.

(customize-version-lessp): New function.

1 files changed, 33 insertions, 0 deletions

diff --git a/lisp/cus-edit.el b/lisp/cus-edit.el
index cac6684cbbb..8a272f6cd0f 100644
--- a/lisp/cus-edit.el
+++ b/lisp/cus-edit.el
@@ -856,6 +856,39 @@ are shown; the contents of those subgroups are initially hidden."
                                 (custom-unlispify-tag-name symbol))))
 
 ;;;###autoload
+(defun customize-changed-options (since-version)
+  "Customize all user option variables whose default values changed recently.
+This means, in other words, variables defined with a `:new' option."
+  (interactive "sCustomize options changed, since version (default all versions): ")
+  (if (equal since-version "")
+      (setq since-version nil))
+  (let ((found nil))
+    (mapatoms (lambda (symbol)
+                (and (boundp symbol)
+                     (let ((version (get symbol 'custom-version)))
+                       (and version
+                            (or (null since-version)
+                                (customize-version-lessp since-version version))))
+                     (setq found
+                           (cons (list symbol 'custom-variable) found)))))
+    (if (not found)
+        (error "No user options have changed defaults in recent Emacs versions")
+      (custom-buffer-create (custom-sort-items found t nil)
+                            "*Customize Changed Options*"))))
+
+(defun customize-version-lessp (version1 version2)
+  (let (major1 major2 minor1 minor2)
+    (string-match "\\([0-9]+\\)[.]\\([0-9]+\\)" version1)
+    (setq major1 (read (match-string 1 version1)))
+    (setq minor1 (read (match-string 2 version1)))
+    (string-match "\\([0-9]+\\)[.]\\([0-9]+\\)" version2)
+    (setq major2 (read (match-string 1 version2)))
+    (setq minor2 (read (match-string 2 version2)))
+    (or (< major1 major2)
+        (and (= major1 major2)
+             (< minor1 minor2)))))
+  
+;;;###autoload
 (defalias 'customize-variable-other-window 'customize-option-other-window)
 
 ;;;###autoload