title: Nice way to check if backbone fetch returns an empty model
body: <p>I am using node.js / express and returning an empty object if no data exists on server (i.e.: res.send({}) on the express side).</p>
  
  <p>However, since I am using Backbone myCollection.fetch(....) 
  I am still get a model back, only that it's empty.</p>
  
  <p>As in:</p>
  
  <pre><code>  _getLines: function () {
    var self = this;
        self.m_linesCollection.fetch({
            success: function (data) {
                $(Elements.FASTERQ_CUSTOMER_LINES).empty();
                if (_.size(data.models["0"].attributes) == 0)
                    return;      
              },
              error: function () {
                  log('error loading collection data');
              }
          });
      }
  </code></pre>
  
  <p>as you can see I am doing a dirty check on client side via:</p>
  
  <p>if (_.size(data.models["0"].attributes) == 0)</p>
  
  <p>which works fine... to check if no real models came back, but I am sure there is a better way to check if model is empty, or send something else from server side :/  ?</p>
  
  <p>Just seems so trivial... I must be missing something...</p>
  
  <p>thx,</p>
  
  <p>Sean.</p>