title: PHP: Assign null if not set?
body: <p>Is there any sort of assign-if-not-empty-otherwise-assign-null function in PHP?</p>
  
  <p>I'm looking for a cleaner alternative to the following:</p>
  
  <pre><code>$variable = (!empty($item)) ? $item : NULL;
  </code></pre>
  
  <p>It would also be handy if I could specify the default value; for instance, sometimes I'd like ' ' instead of NULL.</p>
  
  <p>I could write my own function, but is there a native solution?</p>
  
  <p>Thanks!</p>
  
  <p>EDIT: It should be noted that I'm trying to avoid a notice for undefined values.</p>