/*
  将下面异步代码使用 Promise 的方法改进
  尽量用看上去像同步代码的方式
  setTimeout(function () {
    var a = 'hello'
    setTimeout(function () {
      var b = 'lagou'
      setTimeout(function () {
        var c = 'I ♥ U'
        console.log(a + b +c)
      }, 10)
    }, 10)
  }, 10)
*/
new Promise(function (resolve, reject) {
    resolve("hello");
  })
  .then(value => {
    let b = value + "lagou"
    return b;
  })
  .then(value => {
    let c = value + "IOU";
    console.log(c);
  })
  .catch(reason => console.log(reason))