Causal trees in Haskell
Causal trees, as described by Victor Grishchenko in this paper, are a way of representing a Unicode document such that insertion and deletion patches can be applied in any order, and converge to the same result. This is similar to various operational transformation schemes, but simpler, and easier to guarantee correctness.
This library contains efficient algorithms and data structures for working with causal trees. It's not ready for release yet.