gnus-compat.el (string-bytes): Work for XEmacs

[gnus] / lisp / gnus-compat.el

diff --git a/lisp/gnus-compat.el b/lisp/gnus-compat.el
index 1307488..d286ea1 100644 (file)
--- a/lisp/gnus-compat.el
+++ b/lisp/gnus-compat.el
@@ -1,6 +1,6 @@
 ;;; gnus-compat.el --- Compatability functions for Gnus
 
-;; Copyright (C) 2012 Free Software Foundation, Inc.
+;; Copyright (C) 2012-2015 Free Software Foundation, Inc.
 
 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
 ;; Keywords: compat
@@ -97,6 +97,62 @@ TRASH is ignored."
                           (lambda (process status)
                             (apply function process status args))))))
 
+;; XEmacs 21.4
+(unless (fboundp 'bound-and-true-p)
+  (defmacro bound-and-true-p (var)
+    "Return the value of symbol VAR if it is bound, else nil."
+    (and (boundp var)
+        (symbol-value var))))
+
+
+;; Emacs less than 24.3
+(unless (fboundp 'add-face)
+  (defun add-face (beg end face)
+    "Combine FACE BEG and END."
+    (let ((b beg))
+      (while (< b end)
+       (let ((oldval (get-text-property b 'face)))
+         (put-text-property
+          b (setq b (next-single-property-change b 'face nil end))
+          'face (cond ((null oldval)
+                       face)
+                      ((and (consp oldval)
+                            (not (keywordp (car oldval))))
+                       (cons face oldval))
+                      (t
+                       (list face oldval)))))))))
+
+(unless (fboundp 'move-beginning-of-line)
+  (defun move-beginning-of-line (arg)
+    (interactive "p")
+    (unless (= arg 1)
+      (forward-line arg))
+    (beginning-of-line)))
+
+(unless (fboundp 'delete-dups)
+  (defun delete-dups (list)
+    "Destructively remove `equal' duplicates from LIST.
+Store the result in LIST and return it.  LIST must be a proper list.
+Of several `equal' occurrences of an element in LIST, the first
+one is kept."
+    (let ((tail list))
+      (while tail
+       (setcdr tail (delete (car tail) (cdr tail)))
+       (setq tail (cdr tail))))
+    list))
+
+(unless (fboundp 'declare-function)
+  (defmacro declare-function (&rest r)))
+
+(unless (fboundp 'string-bytes)
+  (defun string-bytes (string)
+    (length (if (or (mm-coding-system-p 'utf-8)
+                   (ignore-errors
+                     (let (mucs-ignore-version-incompatibilities)
+                       (require 'un-define))))
+               (encode-coding-string string 'utf-8)
+             string))))
+
 (provide 'gnus-compat)
 
 ;; gnus-compat.el ends here