bug#13467: 24.3.50; Problem with `advice' show-paren-function

[nyc4bos]

Hi,

While trying to send an email message ^C^C `(message-send-and-exit)',
I got the following error message in the echo area:

Error in timer: (wrong-type-argument characterp nil)

I was not able to send the message and could only abort (^G).

I then got a backtrace which I have included (below).

I suspect this is because of the changes to `advice'.

Here is 'advice' function that I am using:

(defadvice show-paren-function (after show-matching-paren-offscreen
                                      activate)
  "If the matching paren is offscreen, show the matching line in the
echo area. Has no effect if the character before point is not of
the syntax class ')'."
  (interactive)
  (let ((matching-text nil))
    ;; Only call `blink-matching-open' if the character before point
    ;; is a close parentheses type character. Otherwise, there's not
    ;; really any point, and `blink-matching-open' would just echo
    ;; "Mismatched parentheses", which gets really annoying.
    (if (char-equal (char-syntax (char-before (point))) ?\))
        (setq matching-text (blink-matching-open)))
    (if (not (null matching-text))
        (message matching-text))))

Thanks.

Debugger entered--Lisp error: (wrong-type-argument characterp nil)
  char-syntax(nil)
  (char-equal (char-syntax (char-before (point))) 41)
  (if (char-equal (char-syntax (char-before (point))) 41) (setq matching-text 
(blink-matching-open)))
  (let ((matching-text nil)) (if (char-equal (char-syntax (char-before 
(point))) 41) (setq matching-text (blink-matching-open))) (if (not (null 
matching-text)) (message matching-text)))
  (let (ad-return-value) (setq ad-return-value (with-no-warnings (funcall 
ad--addoit-function))) (let ((matching-text nil)) (if (char-equal (char-syntax 
(char-before (point))) 41) (setq matching-text (blink-matching-open))) (if (not 
(null matching-text)) (message matching-text))) ad-return-value)
  ad-Advice-show-paren-function(#[nil
  "\203\336`\306\307`S!!\310=\203





In GNU Emacs 24.3.50.1 (i386-mingw-nt6.1.7601)
 of 2013-01-15 on ODIEONE
Bzr revision: 111532 dmantipov@yandex.ru-20130115101431-o6w1qeqwqcmyxmi9
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --with-gcc (4.7) --no-opt --enable-checking --cflags
 -IC:/Devel/emacs/build/include --ldflags -LC:/Devel/emacs/build/lib'

Important settings:
  value of $LANG: en_US
  locale-coding-system: cp1252
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <menu-bar> <help-menu> 
<send-emacs-bug-report>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

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None found.

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