// 1. Old, sucky way of doing async work: callback hell!
function myCallback(result) {
  this.items = result;
}
someAjaxRequest(myCallback);


// 2. Slightly better way using Promises!
someAjaxRequest().then(results => this.items = results);


// 3. New awesome sexy way: async/await!
this.items = await someAjaxRequest();