你为什么会收到“对象没有属性”的错误消息？

huangapple
go评论99阅读模式
英文:

Why am I getting object has no attribute?

问题

queue.py 文件中存在一个拼写错误，导致了该错误。在 Queue 类的构造函数中，def __int__(self): 应该是 def __init__(self):。请将其更正如下：

  1. class Queue:
  2.     def __init__(self):  # 修正拼写错误
  3.         self._items = deque()
  5.     # 其他类方法不需要更改

这样修正后，你的代码应该能够正常运行而不再出现 "AttributeError" 错误。

英文:

I have written a code that uses python deque from collections. I have created an adapetr class queue.py that handles queue operations. But I am getting error object has no attribute.

queue.py :

  1. from collections import deque
  4. class Queue:
  5.     def __int__(self):
  6.         self._items = deque()
  8.     def enqueue(self, item):
  9.         self._items.append(item)
  11.     def extend(self, *elements):
  12.         self._items.extend(elements)
  14.     def dequeue(self):
  15.         try:
  16.             return self._items.popleft()
  17.         except IndexError:
  18.             raise IndexError("Dequeue from empty queue") from Queue
  20.     def __len__(self):
  21.         return len(self._items)
  23.     def __contains__(self, item):
  24.         return item in self._items
  26.     def __iter__(self):
  27.         yield from self._items
  29.     def __repr__(self):
  30.         return f"Queue({list(self._items)})"

graph.py :

  1. from queue import Queue
  4. def getNodeName(rootName):
  5.     return input(f"Enter child of node {rootName} : ")
  8. def inputChildren(root):
  9.     print(f"Enter stop to stop entering children for node {root} : ")
  10.     child = list()
  11.     while True:
  12.         data = getNodeName(root)
  13.         if data.lower() == "stop":
  14.             break
  15.         child.append()
  16.     return child
  19. def inputGraph():
  20.     graph = dict()
  21.     queue = Queue()
  23.     queue.enqueue(input("Enter root name : "))
  25.     while len(queue) != 0:
  26.         root = queue.dequeue()
  27.         rootChildren = inputChildren(root)
  28.         queue.extend(rootChildren)
  30.         if len(rootChildren) == 0:
  31.             continue
  32.         else:
  33.             graph[root] = rootChildren
  35. if __name__=="__main__":
  36.     print(inputGraph())

Output :

  1. Enter root name : A
  2. Traceback (most recent call last):
  3.   File "D:\graph.py", line 36, in <module>
  4.     print(inputGraph())
  5.   File "D:\graph.py", line 23, in inputGraph
  6.     queue.enqueue(input("Enter root name : "))
  7.   File "D:\queue.py", line 9, in enqueue
  8.     self._items.append(item)
  9. AttributeError: 'Queue' object has no attribute '_items'

I have tried searching online but cannot figure out why I am getting this error.

答案1

得分: 0

  1. from collections import deque
  3. class Queue:
  4.     def __init__(self):
  5.         self._items = deque()
  7.     def enqueue(self, item):
  8.         self._items.append(item)
  10.     def extend(self, *elements):
  11.         self._items.extend(elements)
  13.     def dequeue(self):
  14.         try:
  15.             return self._items.popleft()
  16.         except IndexError:
  17.             raise IndexError("Dequeue from empty queue") from Queue
  19.     def __len__(self):
  20.         return len(self._items)
  22.     def __contains__(self, item):
  23.         return item in self._items
  25.     def __iter__(self):
  26.         yield from self._items
  28.     def __repr__(self):
  29.         return f"Queue({list(self._items)})"
  32. def getNodeName(rootName):
  33.     return input(f"Enter child of node {rootName} : ")
  36. def inputChildren(root):
  37.     print(f"Enter stop to stop entering children for node {root} : ")
  38.     child = list()
  39.     while True:
  40.         data = getNodeName(root)
  41.         if data.lower() == "stop":
  42.             break
  43.         child.append(data)
  44.     return child
  47. def inputGraph():
  48.     graph = dict()
  49.     queue = Queue()
  51.     queue.enqueue(input("Enter root name : "))
  53.     while len(queue) != 0:
  54.         root = queue.dequeue()
  55.         rootChildren = inputChildren(root)
  56.         queue.extend(rootChildren)
  58.         if len(rootChildren) == 0:
  59.             continue
  60.         else:
  61.             graph[root] = rootChildren
  63.     return graph
  65. if __name__=="__main__":
  66.     print(inputGraph())
英文: 
  1. from collections import deque
  4. class Queue:
  5.     def __init__(self):
  6.         self._items = deque()
  8.     def enqueue(self, item):
  9.         self._items.append(item)
  11.     def extend(self, *elements):
  12.         self._items.extend(elements)
  14.     def dequeue(self):
  15.         try:
  16.             return self._items.popleft()
  17.         except IndexError:
  18.             raise IndexError("Dequeue from empty queue") from Queue
  20.     def __len__(self):
  21.         return len(self._items)
  23.     def __contains__(self, item):
  24.         return item in self._items
  26.     def __iter__(self):
  27.         yield from self._items
  29.     def __repr__(self):
  30.         return f"Queue({list(self._items)})"
  33. def getNodeName(rootName):
  34.     return input(f"Enter child of node {rootName} : ")
  37. def inputChildren(root):
  38.     print(f"Enter stop to stop entering children for node {root} : ")
  39.     child = list()
  40.     while True:
  41.         data = getNodeName(root)
  42.         if data.lower() == "stop":
  43.             break
  44.         child.append(data)
  45.     return child
  48. def inputGraph():
  49.     graph = dict()
  50.     queue = Queue()
  52.     queue.enqueue(input("Enter root name : "))
  54.     while len(queue) != 0:
  55.         root = queue.dequeue()
  56.         rootChildren = inputChildren(root)
  57.         queue.extend(rootChildren)
  59.         if len(rootChildren) == 0:
  60.             continue
  61.         else:
  62.             graph[root] = rootChildren
  64.     return graph
  67. if __name__=="__main__":
  68.     print(inputGraph())

huangapple
  • 本文由 发表于 2023年2月18日 02:31:47
  • 转载请务必保留本文链接：https://go.coder-hub.com/75488075.html
  • adapter
  • deque
  • python
匿名

发表评论

匿名网友

:?: :razz: :sad: :evil: :!: :smile: :oops: :grin: :eek: :shock: :???: :cool: :lol: :mad: :twisted: :roll: :wink: :idea: :arrow: :neutral: :cry: :mrgreen:

确定