-extern Lisp_Object Qbefore_change_functions;
-extern Lisp_Object Qafter_change_functions;
-extern Lisp_Object Qfirst_change_hook;
-extern Lisp_Object Qpriority, Qbefore_string, Qafter_string;
-extern Lisp_Object Qchoice, Qrange, Qleft, Qright;
-extern Lisp_Object Qvertical_scroll_bar, Qhorizontal_scroll_bar;