I think a good view rendering library should do just one thing well: Render the UI based on the app's state. It should not care where the state is, and most imp

I think a good view rendering library should do just one thing well: Render the UI based on the app's state. It should not care where the state is, and most importantly it should not handle the state itself. This is nice in theory, but in any non-trivial application, a huge amount of state exists just to support the view. It actually makes sense to keep the view stateful and it's counter-productive to further segregate view-specific state. You can still keep large parts of your UI functional, but the idea that your whole UI should be a function from state to view seems misguided.