Ah yes, that's a great point. I was thinking about adding a shouldAddContext property to CollectionView and EachView, but I felt that was just as bad as this constructor check. 

@wagenet When you say "check the API", you mean check for the existence of some property that only EachView has?

I can easily change this to the instanceof check. I can also add a list of the properties that should be added to the attrs of the childView as an property of EachView and CollectionView.