默认比较表示的 Python 魔术方法？

Question

如果我有一个要为其编写自定义比较函数的类，有没有一种方法可以定义要比较的“内容”而不是单独写出来？

class Version:
    def __init__(self, major, minor, patch):
        self.major = major
        self.minor = minor
        self.patch = patch

    @property
    def version(self):
        return self.major, self.minor, self.patch

    def __eq__(self, other):
        return self.version == other.version

    def __gt__(self, other):
        return self.version > other.version

    def __lt__(self, other):
        return self.version < other.version

有点像，

class Version:
    def __init__(self, major, minor, patch):
        self.major = major
        self.minor = minor
        self.patch = patch

    def __representation__(self):
        return self.major, self.minor, self.patch

...对于所有类似比较的运算符，哪个会使用那个 __representation__？

Answer 1

我不知道有什么方法可以一次性定义所有内容。然而 python 提供了 functools.total_ordering只需要编写 __eq__ 和一种比较魔术方法，然后添加所有其他方法的装饰器。

例子:

@total_ordering
class Version:
    def __init__(self, major, minor, patch):
        self.major = major
        self.minor = minor
        self.patch = patch

    @property
    def version(self):
        return self.major, self.minor, self.patch

    def __eq__(self, other):
        return self.version == other.version

    def __lt__(self, other):
        return self.version < other.version