我什么时候需要在我自己的对象上添加哈希，例如python数据类？

发布于 2025-01-21 01:45:12 字数 519 浏览 3 评论 0原文

我经常发现自己处于两种情况之一。我现在有一个类，是标准类

class myClass:
    def __init__(self, x):
        self.x = x

或数据级别

@dataclass(frozen=True)
class myClass:
    x: float

，我想要的就是能够将这两个类作为键存储在词典中，以便hash在对象本身的瞬间上当（仅当）我使用我存储为键的对象的瞬间查找时（仅当）我查找。

我已经在线阅读了一些，让我感到困惑的是__ eq __操作员。我不知道为什么在这里很重要。我想要的只是字典要通过其ID记住该对象。因此，我的问题是

我需要添加def __hash __（self）：返回id（self）返回到上面的两个对象中的任何一个，还是总是隐含的？
我需要添加__ eq __吗？

原文

I find myself in one of two situations very often. I have a class, either a standard class

class myClass:
    def __init__(self, x):
        self.x = x

or a dataclasss

@dataclass(frozen=True)
class myClass:
    x: float

Now, all I want is to be able to store these two classes as keys in a dictionary, such that the hash is on the instant of the object itself, so look-up will work if (and only if) I look-up using the exact same instant of the object that I stored as key.

I've read online a bit, and what confuses me is the __eq__ operator. I have no idea why that is relevant here. All I want is for dictionaries to remember the object by its id. So, my questions are