title: using dataFilter from jquery .ajax with json data
body: <p>how can i produce a modified vaild JSON data string from the JSON data coming from the ajax call. it is necessary to do this with dataFilter.</p>
  
  <p>retData (data returned) from ajax call is:</p>
  
  <pre><code>{"8":"vacation","7":"birthday","5":"summer","4":"2013","3":"2014","6":"winter","2":"2015","1":"2016"}
  </code></pre>
  
  <p>JS code:</p>
  
  <pre><code>'dataFilter': function (retData, json) {
      console.log('retData='+retData);
      data = [];
      $.map(retData, function (value,key) {
          console.log('indx=i'+key+', value='+value);
          node = {
              'id' : 'i'+key,
              'text' : value,
              'icon' : '/',
              'data' : value,     //'metadata' :  value,
              'state' : {'opened' : false},
              'children' : true
          }
          data.push( node );
      });
      console.log('final-data='+data);
      return data;
      //return JSON.stringify(data);
  }
  </code></pre>
  
  <p>but instead i am getting error in browser console: it seems $.map is having the issue when run in 'dataFilter', it runs fine in 'success' call (but plugin strictly wants processing to be done in 'dataFilter')</p>
  
  <pre><code>TypeError: invalid 'in' operand a
  https://www.localhost.com/jscript/jquery/jquery-2.2.0.min.js
  Line 2
  </code></pre>