ES6的Object的测试

'use strict';
//Object.is()
console.log('test is()');
let ret = Object.is('foo','foo') //true
console.log('ret:',ret)
ret =Object.is({},{}) //false
console.log('ret:',ret)

console.log('test assign()')
var target = {a:1}
var s1 = {a:2,b:3}
var s2 = {b:4,c:5}
ret = Object.assign(target,s1,s2)
console.log('ret:',ret)

//对于嵌套对象，处理方法是替换
target = {a:{b:2,c:3}}
s1 = {a:{b:10}}
ret = Object.assign(target,s1)
console.log('对于嵌套对象，处理方法是替换:',ret)

//对于数组是对应序号位置的覆盖。其实这个可以看成对应key为 0，1，2的替换。
ret = Object.assign([1,2,3],[4,5]) // [4,5,3]
console.log('数组覆盖',ret)

//可以给对象添加属性。
class Pt{
  constructor(x,y){
    Object.assign(this,{x,y})
  }
}
let pt = new Pt(1, 2)
console.log(pt); //Pt { x: 1, y: 2 }

//添加方法
Object.assign(Pt.prototype,{
  toString(){
    return String(this.x) + " , " + String(this.y)
  },

  times(s){
    this.x = s*this.x
    this.y = s*this.y
  }
})
console.log(pt.toString());
pt.times(10);
console.log(pt.toString());