Structure sharing Vector in Haskell

Question

Is the Vector in Haskell structure sharing? In Clojure, modifying the (immutable) vector only takes O(log n) time because it is actually a trie-like structure. (http://hypirion.com/musings/understanding-persistent-vector-pt-1)

Is there an equivalent implementation in Haskell?

Answer 1

Data.Vector is plain arrays with O(n) modification.

At the time there is no equivalent of Clojure's vector.

Data.Sequence is implemented as a finger tree, and it supports a wider range of asymptotically efficient operations than Clojure's vector (O(log(n)) concatenation and splitting, O(1) read/write at both ends), but it's also a bit more heavyweight data structure with more RAM usage and some constant overheads.