继承类的 typescript 返回类型

Question

这就是我想要做的:

class Base{
    clone(){
        //return new instance of the inherited  class 
    }
}

class Derived extends Base{
}

const d1=new Derived();
const d2=d2.clone; // I want d2 to be of type Derived

d2 的克隆方法的返回类型应该是 Derived 类型？

Answer 1

我真的希望有更好的方法，但这是我目前所做的:

class Base{
    clone(): this {
        return new (this.constructor as any)(); 
    }
}

class Derived extends Base {
}

class DerivedAgain extends Derived {

}

const d1=new Derived();
const d2 = d1.clone(); 
const d3 = new DerivedAgain().clone();

d2 是Derived 类型，而d3 是DerivedAgain 类型，正如预期的那样。