类继承的递归错误 [英] Recursion error with class inheritance
问题描述
我有一个文件，其中包含要用于存储API端点的类。
我想使用类的原因是，这样我可以通过键入 api.level2.resources 来访问端点。
I have a file containing classes which I want to use to store API endpoints.
The reason I want to use classes, is so that I can access the endpoints by typing api.level2.resources.
这是文件的外观，其中以 API 为主要类，而 SubEntries 为 child'：
Here is what the file looks like, with API as the main class and SubEntries the 'child':
class API(object):
"""
A class for logging to stdout and/or a file. Supports color output for different log kinds.
"""
def __init__(self):
"""
:param log_to_file: Bool - Whether to log to a file or only to stdout (False)
:param s: String - Log file name without extension for success logs
:param e: String - Log file name without extension for error logs
:param prefix: Bool - Whether to show the prefix or not
:param timestamp: Bool - Whether to show the timestamp or not
:param debug: Bool - Whether to show debug messages or not
"""
self.login = '/login'
self.logout = '/logout'
self.sysRequest = '/sysReq'
self.level2 = SubEntries()
class SubEntries(API):
def __init__(self):
super().__init__()
self.host_info = '/info'
self.resources = '/resources'
但是，当我尝试像这样使用它时：
But, when I try and use it like this:
from src import API
api = API()
print(api.level2.resources)
我收到以下错误：
Traceback (most recent call last):
File "D:/_projects/pynap/new.py", line 4, in <module>
api = API()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
...
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
File "D:\_projects\pynap\src\QAPI.py", line 24, in __init__
super().__init__()
File "D:\_projects\pynap\src\QAPI.py", line 18, in __init__
self.level2 = SubEntries()
RecursionError: maximum recursion depth exceeded while calling a Python object
我很确定解决方案很简单，但我不确定如何将类构造为
I am pretty sure the solution is simple, I am just not sure how to structure the class to be able to use it like I want.
推荐答案
正如我在评论中所说，您正在明确创建一个循环引用，因此在某一点上它达到了Python的递归限制。有很多方法可以避免相似类型对象的递归。最简单的是拥有一个共同的父母，例如：
As I've said in my comment, you're quite explicitly creating a circular reference here so at one point it hits Python's recursion limit. There are a lot of ways to avoid recursion of similar-typed objects. The simplest is to have a common parent, for example:
class BaseAPI(object):
# place here whatever you want common for all API/SubEntry objects
pass
class API(BaseAPI):
def __init__(self):
self.login = '/login'
self.logout = '/logout'
self.sysRequest = '/sysReq'
self.level2 = SubEntries()
class SubEntries(BaseAPI):
def __init__(self):
super(BaseAPI, self).__init__()
self.host_info = '/info'
self.resources = '/resources'
您也可以覆盖 __ getattr __（）/ __ setattr __（ ）/ __ delattr __（）您的 BaseAPI 类中的方法，然后动态评估每个属性访问。您还可以将端点 dict 传递给您的 BaseAPI 类，并使其更新其 self .__ dict __ 从传递的 dict ...
You can also override __getattr__()/__setattr__()/__delattr__() methods in your BaseAPI class and then have every property access dynamically evaluated. You can also pass an 'endpoints' dict to your BaseAPI class and have it update its self.__dict__ to get endpoints from a passed dict...
来获取端点缺乏特异性来建议哪种方法最好。
Your question lacks specificity to suggest what would be the best approach.
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