(while (not tchar)
(message "%s (%s): "
prompt
- (mapconcat (lambda (s) (char-to-string (car s)))
- choice ", "))
+ (concat
+ (mapconcat (lambda (s) (char-to-string (car s)))
+ choice ", ") ", ?"))
(setq tchar (read-char))
(when (not (assq tchar choice))
(setq tchar nil)