DEFVAR_LISP ("history-length", &Vhistory_length,
doc: /* *Maximum length for history lists before truncation takes place.
A number means that length; t means infinite. Truncation takes place
-just after a new element is inserted. Setting the history-length
+just after a new element is inserted. Setting the `history-length'
property of a history variable overrides this default. */);
XSETFASTINT (Vhistory_length, 30);