title: Why does -isMemberOfClass: not work here?
body: <pre><code>NSMutableArray *arr = [NSMutableArray arrayWithCapacity:3];
  
  if ([arr isMemberOfClass:[NSMutableArray class]]) {
      NSLog(@"YEP!!");
  } else {
      NSLog(@"NO!!");
  }
  </code></pre>
  
  <p>I get always "NO!!" in console. I tried with Array, NSNumber, NSString. All of them don't seem to work. That's strange. As I get it from the docs, this method should return YES if I test agains the class of the object which is subject of the testing. I'm using the Foundation.h, not Core Foundation (if it makes any difference anyways).</p>