title: How retrieve an index of an NSArray using a NSPredicate?
body: <p>I would know how retrieve an index of an <code>NSArray</code> using a <code>NSPredicate</code> ?</p>
  <pre><code>NSArray *array = [NSArray arrayWithObjects:
                    @&quot;New-York City&quot;,
                    @&quot;Washington DC&quot;,
                    @&quot;Los Angeles&quot;,
                    @&quot;Detroit&quot;,
                    nil];
  </code></pre>
  <p>Which kind of method should I use in order to get the index of &quot;Los Angles&quot; by giving only a <code>NSString</code>?<br />
  NB: <code>@&quot;Los An&quot;</code> or <code>@&quot;geles&quot;</code> should return the same index.</p>