+(defun notmuch-mua-subject-check ()
+ "Signal an error if the subject seems amiss.
+More precisely, if the subject conforms to
+`notmuch-mua-subject-regexp'.
+
+Typically this is added to `notmuch-mua-send-hook'."
+ (or (save-excursion
+ (message-goto-subject)
+ (message-beginning-of-header t)
+ (not (looking-at-p notmuch-mua-subject-regexp)))
+ (y-or-n-p "Subject may be erroneous – is that okay?")
+ (error "Erroneous subject")))
+