title: Deleting an NSManagedObject in the Main Thread from an NSOperation
body: <p>When invoking <code>deleteObject:</code> on an NSManagedObjectContext on the main thread from an NSOperation, do I also need to reference the objectID on the main thread? Currently I am deleting an NSManagedObject in the main thread from an NSOperation in the following way...</p>
  
  <pre><code>NSManagedObjectContext *mainContext = [[[UIApplication sharedApplication] delegate] managedObjectContext];
  
  - (void)deleteObject:(NSManagedObjectID *)objectID
   {
       // Delete on main context on the main thread
       [mainContext performSelectorOnMainThread:@selector(deleteObject:)
                                withObject:[mainContext objectWithID:objectID]
                             waitUntilDone:YES];
   }
  </code></pre>
  
  <p>It's working but I want to make sure it doesn't blow up on me later. The thing I'm not sure about is if <code>[mainContext objectWithID:objectID]</code> is referencing the NSManagedObjectContext from the NSOperation, or since that method invokation is within the <code>performSelectorOnMainThread:withObject:waitUntilDone:</code> is it all being performed on the main thread?</p>