title: removeClass and addClass simultaneously?
body: <pre><code>return $('.card-number').removeClass('valid').addClass('invalid');
  </code></pre>
  
  <p>I'm returning a function value and I need to both <code>removeClass</code> and <code>addClass</code> at the same time without writing two statements, wonder if thats possible?</p>
  
  <p>I tried this but it isn't working:</p>
  
  <pre><code>return $('.card-number').removeClass('valid').end().addClass('invalid');
  </code></pre>