docs: Eio_mock using datagram sockets

[cdaringe]

problem

i am struggling to discover how to write meaningful tests using a mock net and udp.

discussion

there are omd examples verifying tcp streams, perhaps they could be replicated, tuned for UDP?

[talex5]

There's no mock UDP socket in eio.mock at the moment. I found an old branch adding one and rebased it: https://github.com/ocaml-multicore/eio/compare/main...talex5:eio:mock_datagram?expand=1

Is that useful for you?

[cdaringe]

Thanks! I’ll probably have to go back and read the object stuff in OCaml. I skip it every time it comes up, but it would have been vrry useful recently. I appreciate the response!