不能清空数组扩展类的元素

我正在尝试通过扩展本机 Array 来创建自定义 Array 类，但我不知道如何清空元素，这是我的尝试。

class MyArray extends Array {
  // for simplicity I just included the bit of code that fails.
  reset () {
    this = []; // fails of course
  }
}

const myarray = new MyArray();
myarray.push(1);
myarray.reset(); // fails because it tries to rewrite `this`

我究竟做错了什么 ？

回答

class MyArray extends Array {
  // for simplicity I just included the bit of code that fails.
  reset () {
    this.length = 0;
  }
}

const myarray = new MyArray();
myarray.push(1,2,3,4);

console.log('before', myarray);
myarray.reset();
console.log('after', myarray);