(let ((result (list (car list))))
(do ((x (cdr list) (cdr x))
(splice result
- (cdr (rplacd splice (cons (car x) '() ))) ))
+ (cdr (rplacd splice (cons (car x) '())))))
((atom x)
(unless (null x)
(rplacd splice x))))
(defun copy-alist (alist)
#!+sb-doc
"Return a new association list which is EQUAL to ALIST."
- (if (atom alist)
+ (if (endp alist)
alist
(let ((result
(cons (if (atom (car alist))
(car alist)
- (cons (caar alist) (cdar alist)) )
+ (cons (caar alist) (cdar alist)))
nil)))
(do ((x (cdr alist) (cdr x))
(splice result
(car x)
(cons (caar x) (cdar x)))
nil)))))
- ;; Non-null terminated alist done here.
- ((atom x)
- (unless (null x)
- (rplacd splice x))))
+ ((endp x)))
result)))
(defun copy-tree (object)
((atom subtree) subtree)
(t (let ((car (s (car subtree)))
(cdr (s (cdr subtree))))
- (if (and (eq car (car subtreE))
+ (if (and (eq car (car subtree))
(eq cdr (cdr subtree)))
subtree
(cons car cdr))))))))
;; reached, what is left of LIST2 is tacked onto what is left of
;; LIST1. The splicing operation ensures that the correct
;; operation is performed depending on whether splice is at the
- ;; top of the list or not
+ ;; top of the list or not.
(do ((list1 list1)
(list2 list2)
(x list1 (cdr x))
- (splicex ()))
+ (splicex ())
+ (deleted-y ())
+ ;; elements of LIST2, which are "equal" to some processed
+ ;; earlier elements of LIST1
+ )
((endp x)
(if (null splicex)
(setq list1 list2)
(rplacd splicex list2))
list1)
- (do ((y list2 (cdr y))
- (splicey ()))
- ((endp y) (setq splicex x))
- (cond ((let ((key-val-x (apply-key key (car x)))
- (key-val-y (apply-key key (Car y))))
- (if notp
- (not (funcall test-not key-val-x key-val-y))
- (funcall test key-val-x key-val-y)))
- (if (null splicex)
- (setq list1 (cdr x))
- (rplacd splicex (cdr x)))
- (if (null splicey)
- (setq list2 (cdr y))
- (rplacd splicey (cdr y)))
- (return ())) ; assume lists are really sets
- (t (setq splicey y)))))))
+ (let ((key-val-x (apply-key key (car x)))
+ (found-duplicate nil))
+
+ ;; Move all elements from LIST2, which are "equal" to (CAR X),
+ ;; to DELETED-Y.
+ (do* ((y list2 next-y)
+ (next-y (cdr y) (cdr y))
+ (splicey ()))
+ ((endp y))
+ (cond ((let ((key-val-y (apply-key key (car y))))
+ (if notp
+ (not (funcall test-not key-val-x key-val-y))
+ (funcall test key-val-x key-val-y)))
+ (if (null splicey)
+ (setq list2 (cdr y))
+ (rplacd splicey (cdr y)))
+ (setq deleted-y (rplacd y deleted-y))
+ (setq found-duplicate t))
+ (t (setq splicey y))))
+
+ (unless found-duplicate
+ (setq found-duplicate (with-set-keys (member key-val-x deleted-y))))
+
+ (if found-duplicate
+ (if (null splicex)
+ (setq list1 (cdr x))
+ (rplacd splicex (cdr x)))
+ (setq splicex x))))))
(defun subsetp (list1 list2 &key key (test #'eql testp) (test-not nil notp))
#!+sb-doc