langjt

function debounce(fn, delay) {
  var timeout;
  
  return function() {
   var _this = this;
   var _arguements = arguments;
   clearTimeout(timeout);
   timeout = setTimeout(function() {
     fn.apply(_this, _arguements);
   }, delay);

langjt

setTimeout(function() {
        console.log(1)
}, 0);
new Promise(function(a, b) {
    console.log(2);
    for(var i = 0; i < 1000000; i++) {
        i == 999999 && a();
    }
    console.log(3);
}).then(function() {

langjt

function sleep(milliseconds) {
  var start = new Date().getTime();
  for (var i = 0; i < 1e7; i++) {
    if ((new Date().getTime() - start) > milliseconds){
      break;
    }
  }
}
const start = +new Date;
console.log('Dude!');

langjt

var createPet = function(name) {
  var sex;
  
  return {
    setName: function(newName) {
      name = newName;
    },
    
    getName: function() {
      return name;

langjt

function getPrototypeChain(object) {
    var protoChain = [];
    while (object = object.__proto__) {
        protoChain.push(object);
    }
    protoChain.push(null);
    return protoChain;
}

langjt

function printing() {

   console.log(1);

   setTimeout(function() { console.log(2); }, 1000);

   setTimeout(function() { console.log(3); }, 0);

   console.log(4);
}

langjt

var lang = function(){};

lang.extend = lang.prototype.extend = function(){
    var len = arguments.length,
        target = {},
        options, name, src, copy, clone, i= 0;

    if (len === 1) {
        target = this;
    } else if(len > 1) {

langjt

  function getElementsByClassName(clsName, element) {
      var arr = [];

      var aEle = element.getElementsByTagName('*');

      var re = new RegExp('\\b'+ clsName +'\\b');

      for (var i= 0,len=aEle.length; i<len; i++) {
          if (re.test(aEle[i].className)) {
              arr.push(aEle[i]);

langjt

/* 有一个数n，不用for/while循环，怎么返回[1,2,3,...,n]这样一个数组 */

// 方法一：递归
function recursionLoop(n) {
    var arr = [];

    return (function () {
        arr.unshift(n); // 入队
        n--;
        if (n != 0) {

langjt

/*  a，b两个变量，不用第三个变量来交换两个变量的值 */

// a，b为数字
  var a = 1,
    b = 2;

  a = a + b;
  b = a - b;
  a = a - b;