最近开发遇到一个问题是在python3.7的dataclass中不能使用可变的默认值,错误如下: @dataclassclassFoo: bar: list=[]#ValueError: mutable default <class 'list'> for field a is not allowed: use default_factory 收到这种错误之后,修改为如下即可: fromdataclassesimport( dataclass, field ) @dataclassclass...
最近开发遇到一个问题是在python3.7的dataclass中不能使用可变的默认值,错误如下: @dataclass class Foo: bar: list = [] # ValueError: mutable default <class 'list'> for field a is not allowed: use default_factory 收到这种错误之后,修改为如下即可: from dataclasses import ( dataclass, field )...
ValueError: mutable default <class 'list'> for field players is not allowed: use default_factory dataclass默认阻止使用可变数据做默认值 正如报错提示的一样,这时候field对象就登场了。 from dataclasses import dataclass, field, fields from typing import List @dataclass class Player: name: str number:...
raise ValueError(f'mutable default {type(f.default)} for field ' ValueError: mutable default <class 'fairseq.dataclass.configs.CommonConfig'> for field common is not allowed: use default_factory Code sample Environment fairseq Version ( main): PyTorch Version (e.g., 1.0): 1.13.1 OS (e.g...
当数据不应该被复制时,例如因为数据太大或者函数设计需要在原地更改数据以使调用者受益时,调用list()会很糟糕。在这种情况下,像isinstance(x, abc.MutableSequence)这样的运行时检查将是一个好方法。如果你担心得到一个无限生成器——这不是一个常见问题——你可以先调用len()来检查参数。这将拒绝迭代器,同时安全...
It comes with an API change, a new delete option ignoreStoreReadErrorWithClusterBreakingPotential has been introduced, it is not set by default, this maintains backward compatibility. In order to perform an unsafe deletion of a corrupt resource, the user must enable the option for the delete ...
Documentation The example: dataclasses.html#mutable-default-values @dataclass class D: x: list = [] # This code raises ValueError def add(self, element): self.x += element not only raises the ValueError being discussed, but also an unwan...
ValueError: Non keyword-only attributes are not allowed after a keyword-only attribute (unless they are init=False) 1. 将最后一个属性设置kw_only 参数为True: from attr import attrs, attrib, s,fields @attrs class Point(object): x = attrib(default=0) ...
However, since this default value is susceptible to this python "mutable default argument" bug feature, we should use an immutable instead like this: def make_sandwich(ingredients=None): # initialized ingredients here print("Making a sandwich with ", ingredients) So here's the question. There...
NotImplemented def __ne__(self, other): result = self.__eq__(other) if result is NotImplemented: return NotImplemented else: return not result def __lt__(self, other): if other.__class__ is self.__class__: return (self.a, self.b) (other.a, other.b) else: return Not...