1 665c255d 2023-08-04 jrmu (defun ripple-carry-adder (la lb ls c)
 2 665c255d 2023-08-04 jrmu   (let ((n (length la)))
 3 665c255d 2023-08-04 jrmu     (unless (= n (length lb) (length ls))
 4 665c255d 2023-08-04 jrmu       (error "Expecting all lists of same length"))
 5 665c255d 2023-08-04 jrmu     (labels ((ripple-build (la lb lcin ls lcout)
 6 665c255d 2023-08-04 jrmu 	       (unless (null la)
 7 665c255d 2023-08-04 jrmu 		 (full-adder (car la) (car lb) (car lcin)
 8 665c255d 2023-08-04 jrmu 			     (car ls) (car lcout))
 9 665c255d 2023-08-04 jrmu 		 (ripple-build (cdr la) (cdr lb) (cdr lcin)
10 665c255d 2023-08-04 jrmu 			       (cdr ls) (cdr lcout)))))
11 665c255d 2023-08-04 jrmu       (let ((lcin '()) (lcout '()))
12 665c255d 2023-08-04 jrmu 	(dotimes (i n)
13 665c255d 2023-08-04 jrmu 	  (let ((ci (make-wire)))
14 665c255d 2023-08-04 jrmu 	    (push ci lcin)
15 665c255d 2023-08-04 jrmu 	    (push ci lcout)))
16 665c255d 2023-08-04 jrmu 	(push c lcout)
17 665c255d 2023-08-04 jrmu 	(ripple-build la lb lcin ls lcout)))))