The variables *, **, and *** are maintained by the Lisp read-eval-print loop to save the values of results that are printed each time through the loop.
The value of * is the most recent primary value that was printed, the value of ** is the previous value of *, and the value of *** is the previous value of **.
If several values are produced, * contains the first value only; * contains nil if zero values are produced.
The values of *, **, and *** are updated immediately prior to printing the return value of a top-level form by the Lisp read-eval-print loop. If the evaluation of such a form is aborted prior to its normal return, the values of *, **, and *** are not updated.
(values 'a1 'a2) => A1, A2 'b => B (values 'c1 'c2 'c3) => C1, C2, C3 (list * ** ***) => (C1 B A1) (defun cube-root (x) (expt x 1/3)) => CUBE-ROOT (compile *) => CUBE-ROOT (setq a (cube-root 27.0)) => 3.0 (* * 9.0) => 27.0
Lisp read-eval-print loop.
- (variable), + (variable), / (variable), Section 25.1.1 (Top level loop)
* == (car /) ** == (car //) *** == (car ///)