Add support for nanobind? about xtensor-python

[tdegeus]

I believe that currently this is the blocker : xtensor-stack/xtensor#2366 . It would be amazing if we could get that out of the way. Any help is greatly appreciated!

[tdegeus]

@benbovy I've been using C++17 fine. I would be very much open to support this. Have you had time to experiment?

[benbovy]

@tdegeus good to know C++17 works well. I haven't had the time yet to experiment with this, unfortunately.

[tdegeus]

Understood. Open to a contribution if you are up to it (I guess that ideas could be borrowed from https://github.com/wjakob/nanobind/blob/master/include/nanobind/eigen/dense.h ). Otherwise it will come when one of us finds the time or sufficient urgency

[tdegeus]

Just for the record: I did some experimenting with nanobind's ndarray which should be very similar to what we want, and things like allocation and function calls are indeed way faster (at least a factor two in what I experimented with), and compilation much much faster. I hope to get some time soon to work on this (and I hope even more that someone beats me to it ;))!