您好我试图了解mo程序到底出了什么问题。我为球拍中的队列编写了入队，出队，顶部和大小的代码。我还编写了测试用例来试用模块中的程序。当我尝试通过键入以下命令“racket run-tests.rkt | less”来运行测试用例时，我收到以下错误：
“
default-load-handler：只需要一个module' declaration for队列'，但在：
=== context === 默认加载/使用编译 “
以下是我的三个文件及其中的代码
1- queue.rkt
(module queue racket
(provide make-queue enqueue dequeue top size queue-tests)
(struct queue (front back size) #:mutable #:transparent)
(define (make-queue) (queue null null 0))
(define (enqueue q elt)
(set-queue-back! q (cons elt (queue-back q)))
(set-queue-size! q (+ (queue-size q) 1))
)
(define (dequeue q)
(cond ((eq? (queue-size q) 0) null)
((null? (queue-front q))
(begin
(set-queue-front! q (cdr (reverse (queue-back q))))
(set-queue-back! q null)
(set-queue-size! q (- (queue-size q) 1))))
(else
(begin
(set-queue-front! q (cdr (queue-front q)))
(set-queue-size! q (- (queue-size q) 1))))
)
)
(define (top q)
(cond ((eq? (queue-size q) 0) null)
((null? (queue-front q)) (last (queue-back q)))
(else (car (queue-front q)))))
(define (size q)
(queue-size q))
; Test cases Here
(include "test-queue.rkt")
)
2- test-queue.rkt
#lang racket/base
(require rackunit)
(define queue-tests
(test-suite
"Tests for the Queue"
(test-case "Initial Queue Properties"
(let ((q (make-queue)))
(check-equal? (size q) 0 "Queue initially should have size zero.")
(check-equal? (dequeue q) null "Dequeue on an empty queue returns null")
(check-equal? (size q) 0 "Dequeue on empty queue leaves size as zero")
))
(test-case "One Element queue ---- Functional test"
(let ((q (make-queue)))
(check-equal? (size q) 0 "Stack initially should be of size zero")
(enqueue q 1)
(check-equal? (size q) 1 "Added one element to back of queue")
(check-equal? (top q) 1 "Take a sneak peak at our first element")
(dequeue q)
(check-equal? (size 1) 0 "size should now be zero")
(check-equal? (dequeue q) null "dequeue on empty queue returns null")
))
(test-case "One Element queue --- Internal Test"
(let ((q (make-queue)))
(check-equal? (size q) 0 "queue initially should have size zero.")
(enqueue q 3)
(check-equal? (size q) 1 "Added one element.")
(check-equal? (queue-back q) '(3) "Is the element in the back list?")
(check-equal? (top s) 3 "Look at our one element.")
(check-equal? (queue-front q) '(3) "Is the element in the front list?")
(dequeue s)
(check-equal? (queue-front q) '() "Is the data empty now?")
))
(test-case "Multi Element queue --- Functional Test"
(let ((q (make-queue))
(elts (list 8 6 7 5 3 0 9))
)
(check-equal? (size q) 0 "queue initially should have size zero.")
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size.")
)
))
(test-case "Multi Element queue --- Ebb and Flow Test"
(let ((q (make-queue))
(elts (list 8 6 7 5 3 0 9))
)
(check-equal? (size q) 0 "queue initially should have size zero.")
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, first flow.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size, first ebb.")
)
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, second flow.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size, second ebb.")
)
))
(test-case "Multi Element queue --- Internal Test"
(let ((q (make-queue))
(elts (list 5 8 8 2 3 0 0))
(tmp null)
)
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, second flow.")
(set! tmp (cons i tmp)) ; "push" element to a list
(check-equal? (queue-front q) tmp "Queue data is in correct form.")
)
))
))
3- run-tests.rkt
#lang racket/base
(require "queue.rkt")
(require rackunit/text-ui)
(run-tests queue-tests)
任何有助于发现错误的帮助都将受到赞赏。提前谢谢。
答案 0 :(得分：4)
我认为，您所指的错误可能是由于您的“queue.rkt”文件中的语言级别设置错误而导致的。特别是，所有这三个语言都应该设置为
“使用在源中声明的语言”。
老实说，我真的不确定你为什么把它建成三个单独的模块;我认为这会给你带来额外的困难，但应该可以这样做。
编辑：看起来你有问题。特别是，在定义“大小”后，您有三个近似值。 DrRacket在您运行时不会突出显示此问题吗？
编辑2：哦，你好：你正在使用“包含”。不要使用include。
编辑3：好的，这里：我将您的代码重新格式化为一个文件：
(module queue racket
(require rackunit)
(provide make-queue enqueue dequeue top size)
(struct queue (front back size) #:mutable #:transparent)
(define (make-queue) (queue null null 0))
(define (enqueue q elt)
(set-queue-back! q (cons elt (queue-back q)))
(set-queue-size! q (+ (queue-size q) 1))
)
(define (dequeue q)
(cond ((eq? (queue-size q) 0) null)
((null? (queue-front q))
(begin
(set-queue-front! q (cdr (reverse (queue-back q))))
(set-queue-back! q null)
(set-queue-size! q (- (queue-size q) 1))))
(else
(begin
(set-queue-front! q (cdr (queue-front q)))
(set-queue-size! q (- (queue-size q) 1))))
)
)
(define (top q)
(cond ((eq? (queue-size q) 0) null)
((null? (queue-front q)) (last (queue-back q)))
(else (car (queue-front q)))))
(define (size q)
(queue-size q))
(test-case "Initial Queue Properties"
(let ((q (make-queue)))
(check-equal? (size q) 0 "Queue initially should have size zero.")
(check-equal? (dequeue q) null "Dequeue on an empty queue returns null")
(check-equal? (size q) 0 "Dequeue on empty queue leaves size as zero")
))
(test-case "One Element queue ---- Functional test"
(let ((q (make-queue)))
(check-equal? (size q) 0 "Stack initially should be of size zero")
(enqueue q 1)
(check-equal? (size q) 1 "Added one element to back of queue")
(check-equal? (top q) 1 "Take a sneak peak at our first element")
(dequeue q)
(check-equal? (size 1) 0 "size should now be zero")
(check-equal? (dequeue q) null "dequeue on empty queue returns null")
))
#;(test-case "One Element queue --- Internal Test"
(let ((q (make-queue)))
(check-equal? (size q) 0 "queue initially should have size zero.")
(enqueue q 3)
(check-equal? (size q) 1 "Added one element.")
(check-equal? (queue-back q) '(3) "Is the element in the back list?")
(check-equal? (top s) 3 "Look at our one element.")
(check-equal? (queue-front q) '(3) "Is the element in the front list?")
(dequeue s)
(check-equal? (queue-front q) '() "Is the data empty now?")
))
(test-case "Multi Element queue --- Functional Test"
(let ((q (make-queue))
(elts (list 8 6 7 5 3 0 9))
)
(check-equal? (size q) 0 "queue initially should have size zero.")
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size.")
)
))
(test-case "Multi Element queue --- Ebb and Flow Test"
(let ((q (make-queue))
(elts (list 8 6 7 5 3 0 9))
)
(check-equal? (size q) 0 "queue initially should have size zero.")
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, first flow.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size, first ebb.")
)
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, second flow.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size, second ebb.")
)
))
(test-case "Multi Element queue --- Internal Test"
(let ((q (make-queue))
(elts (list 5 8 8 2 3 0 0))
(tmp null)
)
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, second flow.")
(set! tmp (cons i tmp)) ; "push" element to a list
(check-equal? (queue-front q) tmp "Queue data is in correct form.")
)
))
)
当我运行此代码时，我的一个测试用例中会出现一个相当简单的错误。
更一般地说，我很吃惊，你会写这么多测试代码而不运行它:)。我本人会写一个小测试用例，然后尝试一下，而不是在发现更基本的问题之前完成所有这些工作。我很佩服你的坚韧，但我认为你需要更多的偏执狂：）
如果您遇到更多麻烦，请告诉我。
编辑：根据您的要求分成两个文件。
文件1：queue.rkt
(module queue racket
(provide make-queue enqueue dequeue top size)
(struct queue (front back size) #:mutable #:transparent)
(define (make-queue) (queue null null 0))
(define (enqueue q elt)
(set-queue-back! q (cons elt (queue-back q)))
(set-queue-size! q (+ (queue-size q) 1)))
(define (dequeue q)
(cond ((eq? (queue-size q) 0) null)
((null? (queue-front q))
(begin
(set-queue-front! q (cdr (reverse (queue-back q))))
(set-queue-back! q null)
(set-queue-size! q (- (queue-size q) 1))))
(else
(begin
(set-queue-front! q (cdr (queue-front q)))
(set-queue-size! q (- (queue-size q) 1))))))
(define (top q)
(cond ((eq? (queue-size q) 0) null)
((null? (queue-front q)) (last (queue-back q)))
(else (car (queue-front q)))))
(define (size q)
(queue-size q))
)
文件2：queue-tests.rkt，在同一个目录中：
(module test-queue racket
(require "queue.rkt"
rackunit)
(test-case "Initial Queue Properties"
(let ((q (make-queue)))
(check-equal? (size q) 0 "Queue initially should have size zero.")
(check-equal? (dequeue q) null "Dequeue on an empty queue returns null")
(check-equal? (size q) 0 "Dequeue on empty queue leaves size as zero")
))
(test-case "One Element queue ---- Functional test"
(let ((q (make-queue)))
(check-equal? (size q) 0 "Stack initially should be of size zero")
(enqueue q 1)
(check-equal? (size q) 1 "Added one element to back of queue")
(check-equal? (top q) 1 "Take a sneak peak at our first element")
(dequeue q)
(check-equal? (size 1) 0 "size should now be zero")
(check-equal? (dequeue q) null "dequeue on empty queue returns null")
))
(test-case "One Element queue --- Internal Test"
(let ((q (make-queue)))
(check-equal? (size q) 0 "queue initially should have size zero.")
(enqueue q 3)
(check-equal? (size q) 1 "Added one element.")
(check-equal? (queue-back q) '(3) "Is the element in the back list?")
(check-equal? (top s) 3 "Look at our one element.")
(check-equal? (queue-front q) '(3) "Is the element in the front list?")
(dequeue s)
(check-equal? (queue-front q) '() "Is the data empty now?")
))
(test-case "Multi Element queue --- Functional Test"
(let ((q (make-queue))
(elts (list 8 6 7 5 3 0 9))
)
(check-equal? (size q) 0 "queue initially should have size zero.")
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size.")
)
))
(test-case "Multi Element queue --- Ebb and Flow Test"
(let ((q (make-queue))
(elts (list 8 6 7 5 3 0 9))
)
(check-equal? (size q) 0 "queue initially should have size zero.")
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, first flow.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size, first ebb.")
)
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, second flow.")
(check-equal? (top q) i "Testing top with multiple additions.")
)
(for ((i (reverse elts))
(num (reverse (stream->list (in-range 1 8)))))
(check-equal? (top q) i "Testing top with multiple deletions")
(dequeue q)
(check-equal? (size q) (- num 1) "Testing size, second ebb.")
)
))
(test-case "Multi Element queue --- Internal Test"
(let ((q (make-queue))
(elts (list 5 8 8 2 3 0 0))
(tmp null)
)
(for ((i elts)
(num (in-range 1 8)))
(enqueue q i)
(check-equal? (size q) num "Testing size, second flow.")
(set! tmp (cons i tmp)) ; "push" element to a list
(check-equal? (queue-front q) tmp "Queue data is in correct form.")
)
)))