python - 使用 @dataclass 创建的类中的 Python 实例属性分配

Question

我刚刚开始使用@dataclass 装饰器。这是我没有数据类的实现

class Myclass:

    def __init__(self, path: str = None, company_name: List = None):

        self.path = path
        self.company_name = company_name

        if path is not None:
            with open(self.path, 'r') as f:
                self.data = yaml.load(f, Loader=yaml.FullLoader)
        else:
            self.data = {'company': self.company_name}

所以在这里，我正在做一个实例属性分配。

c = Myclass(path = '/home/akash/project/stock-analysis/data/sample_company.yaml')
c.data
>>>{'company': ['ADANIGREEN', 'HDFCAMC', 'WHIRLPOOL', 'APLAPOLLO', 'LALPATHLAB']}

我管理的@dataclass 等价物是

@dataclass
class Myclass:
    path: str=None
    company_name: List=None
        
    def __post_init__(self):
        if self.path is not None:
            with open(self.path, 'r') as f:
                self.data = yaml.load(f, Loader=yaml.FullLoader)
        else:
            self.data = {'company': self.company_name}

它提供完全相同的输出（这是预期的）

c = Myclass(path = '/home/akash/project/stock-analysis/data/sample_company.yaml')
c.data
>>>{'company': ['ADANIGREEN', 'HDFCAMC', 'WHIRLPOOL', 'APLAPOLLO', 'LALPATHLAB']}

那么，我这样做的方式是否正确？

Answer 1

如果你想data作为一个字段包含，你可以初始化它field(init=False)以表明它的值不是一个参数__init__：

from dataclasses import dataclass, field
from typing import List, Dict
import yaml

@dataclass
class Myclass:
    path: str = None
    company_name: List[str] = None
    data: Dict[str, List[str]] = field(init=False)
        
    def __post_init__(self):
        if self.path is not None:
            with open(self.path, 'r') as f:
                self.data = yaml.load(f, Loader=yaml.FullLoader)
        else:
            self.data = {'company': self.company_name}