Revision: emacs@sv.gnu.org/gnus--devo--0--patch-74

[gnus] / lisp / mm-util.el

diff --git a/lisp/mm-util.el b/lisp/mm-util.el
index 4c778ae..802ad86 100644 (file)
--- a/lisp/mm-util.el
+++ b/lisp/mm-util.el
@@ -893,11 +893,18 @@ Use multibyte mode for this."
 (defmacro mm-with-unibyte-current-buffer (&rest forms)
   "Evaluate FORMS with current buffer temporarily made unibyte.
 Also bind `default-enable-multibyte-characters' to nil.
-Equivalent to `progn' in XEmacs"
+Equivalent to `progn' in XEmacs
+
+NOTE: Use this macro with caution in multibyte buffers (it is not
+worth using this macro in unibyte buffers of course).  Use of
+`(set-buffer-multibyte t)', which is run finally, is generally
+harmful since it is likely to modify existing data in the buffer.
+For instance, it converts \"\\300\\255\" into \"\\255\" in
+Emacs 23 (unicode)."
   (let ((multibyte (make-symbol "multibyte"))
        (buffer (make-symbol "buffer")))
     `(if mm-emacs-mule
-        (let ((,multibyte enable-multibyte-characters)
+        (let ((,multibyte enable-multibyte-characters)
               (,buffer (current-buffer)))
           (unwind-protect
               (let (default-enable-multibyte-characters)