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Using the iOS 13 beta SDK, I'm trying to drive updates to a UICollectionView using a NSFetchedResultsController and the new NSDiffableDataSource APIs as outlined in session 230 - 'Building Apps with Core Data'.Using the NSFetchedResultsController delegate method 'didChangeContent withSnapshot', I'm trying to for cast the NSDiffableDataSourceSnapshotReference to a NSDiffableDataSourceSnapshot as shown in the slides. However, I'm running into a compile error when trying to do so - "Generic parameter 'SectionIdentifierType' could not be inferred in cast to 'NSDiffableDataSourceSnapshot'".func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChangeContentWith snapshot: NSDiffableDataSourceSnapshotReference<NSManagedObjectID, NSString>) { dataSource.apply(snapshot as! NSDiffableDataSourceSnapshot, animatingDifferences: true) }Is Anyone else seeing this error? Any thoughts on how I can get past it?I've also filed a feedback report - FB6135082.Thanks,Andrew