===  ALL USERS PLEASE NOTE  ========================

There has been some confusion concerning MAPCAR.
        (DEFUN MAPCAR (&FUNCTIONAL FCN &EVAL &REST LISTS)
                (PROG (V P LP)
                (SETQ P (LOCF V))
        L       (SETQ LP LISTS)
                (%START-FUNCTION-CALL FCN T (LENGTH LISTS) NIL)
        L1      (OR LP (GO L2))
                (AND (NULL (CAR LP)) (RETURN V))
                (%PUSH (CAAR LP))
                (RPLACA LP (CDAR LP))
                (SETQ LP (CDR LP))
                (GO L1)
        L2      (%FINISH-FUNCTION-CALL FCN T (LENGTH LISTS) NIL)
                (SETQ LP (%POP))
                (RPLACD P (SETQ P (NCONS LP)))
                (GO L)))
We hope this clears up the many questions we've had about it.