title: Objective-C slicing an array gives index out of bounds error
body: <p>Trying to do the following:</p>
  
  <pre><code>NSMutableArray *tmpArr = [_tweets subarrayWithRange:NSMakeRange(0, 10)];
  _tweets = [[NSMutableArray alloc] init]; // added this in trial and error debugging
  _tweets = tmpArr;
  </code></pre>
  
  <p><code>_tweets</code> is an <code>NSMutableArray</code> and I'm trying to grab the first 10 objects from it.</p>
  
  <p>However, I receive the following error:</p>
  
  <pre><code>*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayI objectAtIndex:]: index 157 beyond bounds [0 .. 9]'
  </code></pre>
  
  <p>Any ideas?</p>