title: Understanding Jquery promises
body: <p>I have been looking into Jquery's promises through the use of <code>when</code> and I am wondering if it is capable of fullfilling my scenario or whether I need to rethink how I am doing things.</p>
  
  <p>So I have a backbone.js model with a couple of listeners in like:</p>
  
  <pre><code>this.on('supplier:change', function(){
      $.get('/supplier_details', function(data){
          // fill in some fields here
          anotherAjaxCallInAnotherFunction();
      });
  });
  
  anotherAjaxCallInAnotherFunction: function(){
      // Another Ajax call
  }
  </code></pre>
  
  <p>If I were to use <code>when</code> like so <code>model.set({supplier: 'ss'}).done();</code> would the promise be able to wait until the end of all Ajax calls?</p>
  
  <p>What if I set multiple attributes that needed multiple Ajax calls within my backbone model? Would the promise encapsulate the entire setting of a model?</p>