OCaml "list" with constant append to front and back?

Question

I am new to OCaml, and curious if there is a (standardish) data structure in OCaml equivalent to

http://hackage.haskell.org/package/containers-0.2.0.1/docs/Data-Sequence.html

which provides O(1) prepend and append operations?

Answer 1

I believe this is commonly called a deque.

Here's an implementation in OCaml Batteries Included:

http://ocaml-batteries-team.github.io/batteries-included/hdoc/BatDeque.html

This looks like something similar in Jane Street Core:

https://ocaml.janestreet.com/ocaml-core/111.17.00/doc/core/#Dequeue

These are (I would claim) the two most widely used basic OCaml libraries.