title: Assigning, mutable to immutable array?
body: <p>Would someone be so kind as to confirm that I am understanding this correctly. My initial response to this was that the mutableArray when assigned to an immutableArray would become an immutableArray, however this is not the case.</p>
  
  <p>Is this because the initial array is allocated as a mutableArray and the immutableArray is just assigned to point to the same object. The compiler gives a warning, but the the code executes just fine at runtime.</p>
  
  <pre><code>NSMutableArray *mArray = [NSMutableArray arrayWithObjects:@"Teddy", @"Dog", nil];
  NSArray *iArray = mArray;
  [iArray addObject:@"Snoss"]; // Normally this would crash NSArray
  </code></pre>
  
  <p>much appreciated</p>
  
  <p>gary.</p>