+ (cond
+ ((if (and (boundp 'completion-fail-discreetly)
+ (fboundp 'completion-at-point))
+ (let ((completion-fail-discreetly t)) (completion-at-point))
+ (funcall (or (message-completion-function) #'ignore)))
+ ;; Completion was performed; nothing else to do.
+ nil)
+ (message-tab-body-function (funcall message-tab-body-function))
+ (t (funcall (or (lookup-key text-mode-map "\t")
+ (lookup-key global-map "\t")
+ 'indent-relative)))))
+
+(defvar mail-abbrev-mode-regexp)
+
+(defun message-completion-function ()