this.callbacks;// array of functions reference
this.callbacks.forEach(function(callback){
    window.setTimeout(function(){
          callback(data);
    },0);
});

this questions中使用setTimeout的一个示例

resolve: function (data) {
    this.promise.okCallbacks.forEach(function(callback) {
      window.setTimeout(function () {
        callback(data)
      },0);
    });
  },

通过setTimeout调用循环函数与callback()之间的区别是什么？或callback.call();