title: CoreData predicate: string property length?
body: <p>Say if I have an entity <code>Fragment</code>, it has an attribute 'text' which is a string, I want to query the list of <code>Fragment</code> whose <code>text</code> is of length 5:</p>
  
  <pre><code>[NSPredicate predicateWithFormat:@"position == %@ AND text.length == %d", pos, 5];
  </code></pre>
  
  <p>It does not work (ie returns no result), but if I remove text.length in the query it works and I'm certain that there are texts of length 5, so what do I need to change it to?</p>
  
  <p>Thanks!</p>