类的继承

class People {  name: string;
  age: number;
  constructor(name: string, age: number) {
    this.name = name;
    this.age = age;
  }
  eat(food: string): void {
    console.log("eat", food);
  }
}
class Student extends People {
  school: string;
  constructor(name: string, age: number, school: string) {
    super(name, age);
    this.school = school;
  }
}
let stu = new Student("lisi", 19, "qinghua");
stu.eat("apple");