typescript - TypeScript 类实现接口

Question

为什么下面的代码可以正确编译，而不是编译器报错Type '() => number' is not assignable to type '() => void'.？

 interface ClockInterface {
      currentTime: Date;
      f() : void;
    }
    
    class Clock implements ClockInterface {
      sdd : unknown = undefined
      currentTime: Date = new Date();
       f():number{
             return 8
       }
      constructor(h: number, m: number){}
    }

标签： typescript