The Problem of Diffing Two Trees in React

There's already existing knowledge and computer science around how you can use immutable data structures to determine that something very deep within it is unchanged. So there's a lot of work from Rich Icky on enclosure. Another interesting data point is Git, the virtual control system, where basically you don't have to transfer objects that you are guaranteed to already have. But the principle with immutable data structures is that if you have something of ID, like a reference or hash, that tells you that something about the entire subtree of the structure,. You can compare just that ID to see to learn something about the whole tree.