Function: message-strip-subject-re
message-strip-subject-re is a byte-compiled function defined in
message.el.gz.
Signature
(message-strip-subject-re SUBJECT)
Documentation
Remove "Re:" from subject lines in string SUBJECT.
This uses mail-re-regexps, matching is done case-insensitively.
Probably introduced at or before Emacs version 31.1.
Source Code
;; Defined in /usr/src/emacs/lisp/gnus/message.el.gz
(defun message-strip-subject-re (subject)
"Remove \"Re:\" from subject lines in string SUBJECT.
This uses `mail-re-regexps', matching is done case-insensitively."
(let ((case-fold-search t))
(if (string-match message-subject-re-regexp subject)
(substring subject (match-end 0))
subject)))