fromtypingimportProtocol, runtime_checkable @runtime_checkable# 运行时类型检查 classQuackable(Protocol): defquack(self) ->str: # 定义鸭子叫的协议方法 ... # 无需显式继承 Quackable classDuck: defquack(self) ->str: # 实现鸭子叫的具体方法...
12. 协议和结构化类型(Duck Typing) fromtypingimportProtocol, runtime_checkable @runtime_checkable classSupportsClose(Protocol): def close(self) ->None: ... def close_all(items:list[SupportsClose]) ->None: for item in items: item.close() 13. 装饰器高级用法 # 带参数的装饰器 defrepeat(num...
Python 3.8 引入了typing.Protocol类与typing.runtime_checkable装饰器,可以用来定义类型,然后在运行时对对象进行类型检查。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 from typingimportProtocol,runtime_checkable from dataclassesimportdataclass @runtime_checkableclassHasName(Protocol):name:str defsay_hell...
第二个方式是定义一个协议,然后做协议检查 from typing import runtime_checkable,Protocol @runtime_checkable class DuckLike(Protocol): """会叫的东西""" def sing(self) -> None: ... class Duck(): def sing(self): print("I am a duck") class Bird(): def sing(self): print("I am a b...
After decorating your Shape protocol class with @runtime_checkable, the built-in isinstance() function works as you wanted. Remove ads Conclusion Now you know how to use protocols in Python. Protocols let you define a type relationship between objects without the burden of inheritance. This relat...
import typing # 定义Printable协议，需要具有打印方法 @typing.runtime_checkable class Printable(Protocol...
默认情况下,这只对类型检查器起作用,但如果你应用typing.runtime_checkable(),你也可以对它们执行isinstance()检查。 上节中的例子如下: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 from typingimportProtocol,runtime_checkable @runtime_checkableclassReader(Protocol):defread(self)->str:...classFooRead...
根据isinstance的默认规则,这使得Duck1()成为DuckProtocol的实例。 Runtime-checkable协议定义它们自己的isinstance逻辑(通过实现__instancecheck__),但是如果该逻辑不能确定对象是协议的实例,那么它将通过委托给super().__instancecheck__而不是返回False来结束。经过大量的间接操作和委托之后,我们最终进入了_abc._abc_...
from typing import Protocol, runtime_checkable, Any @runtime_checkable class RandomPicker(Protocol): def pick(self) -> Any: ... 注意 pick方法返回Any。在“实现通用静态协议”中,我们将看到如何使RandomPicker成为一个带有参数的通用类型,让协议的使用者指定pick方法的返回类型。 示例13-19。randompick_te...
@runtime_checkable class SupportsComplex(Protocol): """An ABC with one abstract method __complex__.""" __slots__ = () @abstractmethod def __complex__(self) -> complex: pass 关键在于__complex__抽象方法。¹⁸ 在静态类型检查期间,如果一个对象实现了只接受self并返回complex的__complex__...