小编nic*_*hen的帖子

我正在尝试创建冻结的数据类，但在设置中的值时遇到问题__post_init__。有没有办法从设置基于值的字段值init param在dataclass使用时frozen=True设置？

RANKS = '2,3,4,5,6,7,8,9,10,J,Q,K,A'.split(',')
SUITS = 'H,D,C,S'.split(',')


@dataclass(order=True, frozen=True)
class Card:
    rank: str = field(compare=False)
    suit: str = field(compare=False)
    value: int = field(init=False)
    def __post_init__(self):
        self.value = RANKS.index(self.rank) + 1
    def __add__(self, other):
        if isinstance(other, Card):
            return self.value + other.value
        return self.value + other
    def __str__(self):
        return f'{self.rank} of {self.suit}'

这就是痕迹

 File "C:/Users/user/.PyCharm2018.3/config/scratches/scratch_5.py", line 17, in __post_init__
    self.value = RANKS.index(self.rank) + 1
  File "<string>", line 3, in __setattr__
dataclasses.FrozenInstanceError: cannot assign …