了解数据级字段使用
我对Dataclasses中字段（）的使用方式的使用方式感到困惑。 我有这个（毫无意义的）示例：
from dataclasses import dataclass, field
@dataclass
class Person:
name: str = field(init=False)
def print_name(self):
print(self.name)
dieter = Person()
dieter.print_name()
我希望这会创建一个空字符串。但是，只有当我添加参数默认值=“”时才发生。 甚至在pycharm中，没有语法突出显示时，当我编写以下代码时：
name: int = field(init=False, default="")
如果没有语法突出显示，那么类型提示的点是什么？ 我真的没有任何问题，我只是想掌握，实际上正在发生的事情。
使用情况是，我正在创建一个类，后来包含matplotlib轴，绘图等。由于它们在开始时不存在，所以我只想初始化它们，因此它们已连接到类，以后可以是创建。
I am confused about how the usage of field() in dataclasses works.
I have this (senseless) example:
from dataclasses import dataclass, field
@dataclass
class Person:
name: str = field(init=False)
def print_name(self):
print(self.name)
dieter = Person()
dieter.print_name()
I would expect this to create an empty string. However, this only happens, when I add the parameter default="".
Evenmore, in pycharm, no syntax highlight complains, when I write following code:
name: int = field(init=False, default="")
What is the point of type hints, if there is not syntax highlighting?
I don't really have any problem, I'm just trying to grasp, what is actually happening.
The usage case is, that I am creating a class, that later contains matplotlib axes, plots etc. Since they don't exist in the beginning, I only want to initialize them, so they are connected to the class, and can later be created.
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从文档（强调地雷）中：
因此，该类型提示主要用作标志来告诉
dataclass以注意该名称。这两个例外是注释是
classVar或initvar，用于指示名称不是实例属性，而是class属性或init-horly commine cam分别。我认为的第三个例外是Python 3.10中引入的新
kw_only值，这表明不能将以下字段作为位置参数传递到__ INT __ INT __ INT __。 （因此，“字段”是这样的，根本没有定义字段，但它仍然是一个装饰的名称，其类型dataclass待注意。）From the documentation (emphasis mine):
So the type hint is mainly used as a flag to tell
dataclassto pay attention to the name.The two exceptions are if the annotation is
ClassVarorInitVar, used to indicate that the name is not an instance attribute, but either a class attribute or an init-only parameter, respectively.What I consider a third exception is the new
KW_ONLYvalue introduced in Python 3.10, which indicates that the following fields cannot be passed as positional arguments to__init__. (The "field" so annotated doesn't define a field at all, but it's still a decorated name whose typedataclasspays attention to.)