title: RxJS flatMapLatest is not a function
body: <p>Using <code>RxJs</code> I am trying to reproduce a demo. But i am not getting any result. Instead getting error as : <code>distinct.flatMapLatest is not a function</code></p>
  
  <p>what is wrong i did here? do i required to add any <code>library</code> here?</p>
  
  <p>here is my try: but look in to demo to get real issue what is face.</p>
  
  <pre><code>$(document).ready(function(){
  
  var $input = $('#input'),
      $results = $('#results');
  
  var keyups = Rx.Observable.fromEvent($input, 'keyup')
      .map(e =&gt; e.target.value)
      .filter(text =&gt; text.length &gt; 2);
  
  var throttled = keyups.throttle(500);
  
  var distinct = throttled.distinctUntilChanged();
  
  function searchWikipedia (term) {
      return $.ajax({
          url: 'http://en.wikipedia.org/w/api.php',
          dataType: 'jsonp',
          data: {
              action: 'opensearch',
              format: 'json',
              search: term
          } 
      }).promise();
  
  }
  
  
  var suggestions = distinct.flatMapLatest(searchWikipedia);
  
  suggestions.subscribe(data =&gt; {
      var res = data[1];
      /* Do something with the data like binding */
      $results.empty();
  
      $.each(res, (_, value) =&gt; $('&lt;li&gt;' + value + '&lt;/li&gt;').appendTo($results));
  }, error =&gt; {
      /* handle any errors */
      $results.empty();
  
      $('&lt;li&gt;Error: ' + error + '&lt;/li&gt;').appendTo($results);
  
  });
  
  })
  </code></pre>
  
  <p><a href="http://plnkr.co/edit/7LUL7UMeRZVTPFpSr5aU?p=preview" rel="noreferrer">Live Demo</a></p>