SOURCE

// 新写法， 直观，简洁，适合不需要传参的类
class Person1 {
  name = 'lily'
  age = 20
  speak() {
    console.log(`my name is ${this.name}, I am ${this.age} years old`)
  }
}

// 可以传参，但是要多写一个constructor
class Person2 {
  constructor(name, age) {
    this.name = name
  	this.age = age
  }
  speak() {
    console.log(`my name is ${this.name}, I am ${this.age} years old`)
  }
}

const person1 = new Person1()
const person2 = new Person2('kuohao', 22)

person1.speak()
person2.speak()