让setTimeout支持链式

修改很简单，通过参数判断，然后返回下promise对象

(function() {
  var timeout = setTimeout;
  window.setTimeout = function(fn, time) {
    if (!time) {
      time = fn;
      return $.Deferred(function(dfd) {
        timeout(function() {
          dfd.resolvel(dfd);
        }, time);
      }).promise();
    }
    timeout.apply(window, arguments);
  }
})();

 

调用

setTimeout(1000).done(function(dnt) {
  console.log(dnt)
})