; Double frying the baked tomatoes (nested atom duplication)
; ------------------------------
; The Little Lisper 3rd Edition
; Chapter 6
; Exercise 3
; Common Lisp
; http://t...content-available-to-author-only...r.com/thelittlelisper
; http://t...content-available-to-author-only...t.com/2010/06/little-lisper-chapter-6-oh-my-gawd-its.html
; http://t...content-available-to-author-only...t.com/2010/06/little-lisper.html
; ------------------------------
(setf l1 '((fried potatoes)(baked (fried)) tomatoes))
(setf l2 '(((chili) chili (chili))))
(setf l3 '())
(setf lat1 '(chili and hot))
(setf lat2 '(baked fried))
(setf a 'fried)
; ------------------------------
(defun double (a lat)
(cond
((null lat) '())
((eq (car lat) a)(cons a lat))
(t (cons (car lat)
(double a (cdr lat))))))
(print (double 'bob '(bob the builder)))
(defun notatom (lat)
(not (atom lat)))
(defun double* (a lat)
(cond
((null lat) '())
((notatom (car lat))
(cons (double* a (car lat))
(double* a (cdr lat))))
((eq (car lat) a)(cons a lat))
(t (cons (car lat)
(double* a (cdr lat))))))
(print (double* 'bob '(bob the builder)))
;(BOB BOB THE BUILDER)
(print (double* 'bob '((bob) the builder)))
;((BOB BOB) THE BUILDER)
(print (double* a l1))
;((FRIED FRIED POTATOES) (BAKED (FRIED FRIED)) TOMATOES)
(print (double* a l2))
;(((CHILI) CHILI (CHILI)))
(print (double* a lat2))
;(BAKED FRIED FRIED)