Default argument value is mutable 这是因为,在Python中,当函数参数使用可变类型(如列表、字典、集合等)作为默认值时,可能会遇到一个问题,即这些默认值在函数被多次调用时可能会被意外修改。这是因为Python在函数定义时计算一次默认值,并在之后的调用中重复使用这些默认值,而不是每次调用时都重新创建它们。 示例问题...
2、The Python Tutorial The default value is evaluated only once. This makes a difference when the default is a mutable object such as a list, dictionary, or instances of most classes. For example, the following function accumulates the arguments passed to it on subsequent calls 解决方案: 参考...
@文心快码BaiduComatedefault argument value is mutable 文心快码BaiduComate 1. 解释什么是默认参数值 在Python中,函数定义时可以指定某些参数具有默认值。当调用函数时,如果未提供这些具有默认值的参数,则函数将使用这些默认值进行执行。默认参数值在函数定义时计算一次,并在函数多次调用之间保持不变,除非显式地通过...
python 函数里面使用[]作为默认参数时,会提示Default Argument Value is mutable(默认参数值是可以改变的) 每次执行函数的时候,可能会不断累加(如果函数里面有append或extend方法),这其实不是我们想要的 解决: 我们可以把它作为None,然后代码里面写逻辑 ** 一定要注意python的可变类型 ...
警告:Default Argument Value is mutable 产生原因 参数赋值为可变对象(mutableobject),比如list; 函数参数的初值只会被计算一次。 参考案例 解决方法
The most useful form is to specify a default value for one or more arguments. This creates a function that can becalled with fewer argumentsthan it is defined to allow. For example: 最有用的形式就是对一个或多个参数指定( specify )一个 预设值 (default value)。这样就会构建一个相比调用定义...
Detector ID python/default-argument-mutable-objects@v1.0 Category Code Quality Common Weakness Enumeration (CWE) - Tags #maintainability Noncompliantexample 1# Noncompliant: default arguments have mutable objects.2defwith_complex_default_value_noncompliant(self, index=1, mydict={},3mylist=[]):4mydic...
As we continue our look at places outside of a Boolean context where we can use the or operator, we’re now going to take a look at how the or operator can help us when we’re trying to write a function whose intent is to modify the argument value…
In django/test/client.py there are several methods that have data={} in their argument lists. The {} dictionary is a mutable type and it is not recommended to use mutable objects as default arguments. This is because each invocation of the method where data is not specified will use the...
Context: Ubuntu 21.10 flet 0.1.48 Python 3.11.0b4 I was trying to follow the introduction and I received this traceback: >> python3 app.py Traceback (most recent call last): File "/home/nsukami/GIT/flet_example/app.py", line 1, in <modul...