Python Strict Interfaces

安装

pip install strict-interfaces

设计目标

• 尽可能严格
• 在导入时失败
• 不干涉 object 和/或 type 继承
• 可集成到CPython Core
• 无论解释器是否支持，都能“开箱即用”

功能

• 类定义上的特殊关键字 implements
• 多接口实现
• 隐式接口实现
• 受限的重载的接口继承
• 类似于 issubclass 的特殊 isimplementation 函数
• 部分 issubclass 支持（见下文）
• 限制创建接口实例
• 限制同时从 object 和 interface 继承

使用方法

显式实现

class TestInterface(interfaces.interface):
    def method(self, arg: typeT1) -> typeT2:
        pass

class TestClass(interfaces.object, implements=[TestInterface]):
    def method(self, arg: typeT1) -> typeT2:
        pass

未实现时引发异常

class TestInterface(interfaces.interface):
    def method(self, arg):
        pass

class TestClass(interfaces.object, implements=[TestInterface]):
    pass

隐式实现和运行时检查

class TestInterfaceA(interfaces.interface):
    def method_a(arg: typeT1) -> typeT1:
        pass

class TestInterfaceB(interfaces.interface):
    def method_b(arg: typeT2) -> typeT2:
        pass

class TestClass:
    def method_a(arg: typeT1) -> typeT1:
        pass

    def method_b(arg: typeT2) -> typeT2:
        pass

assert interfaces.isimplementation(TestClass, (TestInterfaceA, TestInterfaceB))

isimplementation 检查是否实现了所有接口

class TestInterfaceA(interfaces.interface):
    def method_a(arg: typeT1) -> typeT1:
        pass

class TestInterfaceB(interfaces.interface):
    def method_b(arg: typeT2) -> typeT2:
        pass

class TestClass:
    def method_a(arg: typeT1) -> typeT1:
        pass

# NOTE: In this case `isimplementation` behaves different than `issubclass`
assert not interfaces.isimplementation(TestClass, (TestInterfaceA, TestInterfaceB))
assert issubclass(TestClass, (TestInterfaceA, TestInterfaceB))

贡献

欢迎提出拉取请求、功能请求和错误报告！

github.com/lig/python-interfaces