an object.

implementation-dependent.

The variables +, ++, and +++ are maintained by the Lisp read-eval-print loop to save forms that were recently evaluated.

The value of + is the last form that was evaluated, the value of ++ is the previous value of +, and +++ is the previous value of ++.

(+ 0 1) 

→

1



(- 4 2) 

→

2



(/ 9 3) 

→

3



(list + ++ +++) 

→

((/ 9 3) (- 4 2) (+ 0 1))



(defparameter *a* 1) 

→

*A*



(defparameter *b* 2) 

→

*B*



(defparameter *c* 3) 

→

*B*



(defparameter *d* (list *a* *b* *c*)) 

→

*D*



(setf *a* 4 *b* 5 *c* 6 *d* (list a b c)) 

→

(4 5 6)



(list *a* *b* *c*) 

→

(4 5 6)



(eval +++) 

→

(1 2 3)



#.`(,@++ *d*) 

→

(1 2 3 (1 2 3))

Lisp read-eval-print loop.

Variable -, Variable *, Variable/, {\secref\TopLevelLoop}

None.