It's not straightforward. Look at all the occurrences of `collectionView` below, which is a `UICollectionView`. To extract code to use for `ReactiveTableViewSource` we'd need a common interface between `UICollectionView` and `UITableView` that has all the appropriate methods. The solutions I can see are not super elegant, like passing all those common methods as functions, though it would certainly be _DRY_er. Would you like something like that, or have another idea?