Thank you, that is a very nice implementation! I think the key is that the vector library is very well designed - it has certainly been the cause of the majori

Thank you, that is a very nice implementation! I think the key is that the vector library is very well designed - it has certainly been the cause of the majority of my Haskell performance successes. I'll say that your implementation benefits from being able to access partitioning as a library function - the actual implementation of unstablePartition is not particularly pretty (but it is conceptually simple).