title: filtering JSON using underscore
body: <p>I got a JSON name collection like this:</p>
  
  <pre><code>[{
  
     "name":"Jim",
     "prize":"Nokia Mobile"
    },
    {
  
     "name":"Marry",
     "prize":"iPhone"
    },
    {
  
     "name":"Alice",
     "prize":"iPad"
    }
  
  ]
  </code></pre>
  
  <p>now I'd like to filter this JSON by a string: var data= "m";</p>
  
  <p>so, this is what I've done:</p>
  
  <pre><code>    var data= "m";
  
      collection = _.filter(collection,function(c){
  
  
          return _.any(c,function(k){
  
  
              return k.name.toLowerCase().indexOf(data.toLowerCase()) != -1;
  
          });
  
  
      });
  </code></pre>
  
  <p>so, in this case, collection return elements which has m in their name.</p>
  
  <p>However, I've got "Cannot call method 'toLowerCase' of undefined".</p>
  
  <p>I tried to put an alert "alert(c.name);" before the last return, and it's return "undefined". It shouldn't be, isn't it?</p>
  
  <p>what need I change to fix this?</p>