/**
- instanceof 检测原型链，
- Object.create(proto) */
const fn = function() {}
const obj = {}
const sym = Symbol()
const reg = /^kkl/
const map = new Map()
const set = new Set()
const arr = []
console.log(typeof 'jm'); console.log(typeof 20); console.log(typeof true); console.log(typeof null); console.log(typeof undefined); console.log(typeof new Date); console.log(typeof fn); console.log(typeof sym); console.log(typeof reg); console.log(typeof map); console.log(typeof set); console.log(typeof arr);
const noobj = Object.create(null) console.log(map instanceof Map); console.log(set instanceof Set); console.log(map instanceof Map); console.log(map instanceof Map); console.log(noobj instanceof Object);
