blob: 821d0b6ca8b0be49894f35bf3185ee68edc0b937 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
(define-namespace linked-list
(define-record-type linked-list
(linked-list head tail)
linked-list?
(head get-head set-head!)
(tail get-tail set-tail!))
(define (new) (linked-list '() '()))
(define (empty? lst) (null? (get-head lst)))
(define (linked-list->list lst) (get-head lst))
(define (push-first lst val)
(let ((container (list val)))
(set-head! lst container)
(set-tail! list container)))
(define (push-head lst val)
(if (empty? lst)
(push-first lst val)
(set-head! lst (cons val (get-head lst)))))
(define (push-tail lst val)
(if (empty? lst)
(push-first lst val)
(let ((container (list val)))
(set-cdr! (get-tail lst) container)
(set-tail! lst container))))
(export new empty?
push-head push-tail
linked-list->list))
|
