2.14抽象类

abstract class Geom {
  getType() {
    return "Gemo";
  }
  width: number;
  abstract getArea(): number; // 抽象方法
}
class Circle extends Geom {
  getArea() {
    return 123;
  }
}
class Square {}

interface Person8 {
  name: string;
}
interface Teacher8 extends Person8 {
  teacheringAge: number;
}
interface Student8 extends Person8 {
  age: number;
}
const teacher8 = {
  name: "dell8",
};
const student8 = {
  name: "lee8",
  age: 15,
};
const getUserInfo = (user: Person8) => {
  console.log(user.name);
};
getUserInfo(teacher8);
getUserInfo(student8);