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sys-base.lisp (set-command-line-arguments): Rewrite to use `uiop' properly.
[lisp]
/
queue.lisp
diff --git
a/queue.lisp
b/queue.lisp
index 03de43345c8841db30e48ff2759ee4588498b275..44ec5343b0a37382ef12e43195d209ac9e468aec 100644
(file)
--- a/
queue.lisp
+++ b/
queue.lisp
@@
-22,10
+22,10
@@
;;; Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
(defpackage #:queue
;;; Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
(defpackage #:queue
- (:use #:common-lisp)
- (:export #:make-queue #:queue-emptyp #:enqueue #:dequeue))
+ (:use #:common-lisp))
(in-package #:queue)
(in-package #:queue)
+(export 'make-queue)
(defun make-queue ()
"Make a new queue object."
;; A queue is just a cons cell. The cdr is the head of the list of items
(defun make-queue ()
"Make a new queue object."
;; A queue is just a cons cell. The cdr is the head of the list of items
@@
-35,16
+35,27
@@
(defun make-queue ()
(let ((q (cons nil nil)))
(setf (car q) q)))
(let ((q (cons nil nil)))
(setf (car q) q)))
+(export 'queue-emptyp)
(defun queue-emptyp (q)
"Answer whether the queue Q is empty."
(null (cdr q)))
(defun queue-emptyp (q)
"Answer whether the queue Q is empty."
(null (cdr q)))
+(export 'enqueue)
(defun enqueue (x q)
"Enqueue the object X into the queue Q."
(let ((c (cons x nil)))
(setf (cdr (car q)) c
(car q) c)))
(defun enqueue (x q)
"Enqueue the object X into the queue Q."
(let ((c (cons x nil)))
(setf (cdr (car q)) c
(car q) c)))
+(export 'pushqueue)
+(defun pushqueue (x q)
+ "Push the object X onto the front of the queue Q."
+ (let* ((first (cdr q))
+ (new (cons x first)))
+ (setf (cdr q) new)
+ (unless first (setf (car q) new))))
+
+(export 'dequeue)
(defun dequeue (q)
"Remove and return the object at the head of the queue Q."
(if (queue-emptyp q)
(defun dequeue (q)
"Remove and return the object at the head of the queue Q."
(if (queue-emptyp q)
@@
-74,10
+85,12
@@
(defun test-queue ()
(let ((q (make-queue))
(want nil))
(dotimes (i 10000)
(let ((q (make-queue))
(want nil))
(dotimes (i 10000)
- (case (random
2
)
+ (case (random
3
)
(0 (setf want (nconc want (list i)))
(enqueue i q))
(0 (setf want (nconc want (list i)))
(enqueue i q))
- (1 (if (null want)
+ (1 (push i want)
+ (pushqueue i q))
+ (2 (if (null want)
(assert (queue-emptyp q))
(progn
(let ((j (dequeue q))
(assert (queue-emptyp q))
(progn
(let ((j (dequeue q))