I have done this very fast, so it's not really good (slow)…
Yep, i know it's not good, but it could be interesting.
If someone rewrite, it would be nice ! (i have not time to work on it)
Frank, do you have somewhere an abstraction to order list (asc and desc). Maybe you could add it in list-abs library, or i miss something (of course, i think my abstraction need to be rewrite) ?