OCaml Weekly News

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Here is the latest OCaml Weekly News, for the week of August 20 to 27, 2019.

Table of Contents


jserot announced

This is to announce the availability of version 0.6 of Lascar, a library for manipulating Labeled Transition Systems in OCaml.

This release is essentially a repackaging to support building and installing with dune and removing the dependency on camlp4.

Lascar is available in source code from github or as a opam package.

Lwt 4.3.0 — preparing for 5.0.0

Anton Bachin announced

We are pleased to announce release 4.3.0 of Lwt, the promise and concurrent I/O library. It is now installable from opam:

opam update && opam upgrade lwt


Lwt 4.3.0 is a relatively small release, offering a few improvements. However, it announces several new breaking changes for the upcoming Lwt 5.0.0. Everything is detailed in the full changelog. Lwt 5.0.0 is planned for November 2019, three months from now.

The breaking changes are relatively minor and should affect few users. About half are simply removing unused features, some of which are experimental features that never matured.

There are two breaking changes planned for 5.0.0 that are probably relevant to everyone:

  1. The signature of Lwt.async will become

    Lwt.async : (unit -> unit Lwt.t) -> unit

    See #603.

  2. Lwt.choose, Lwt.pick, and similar functions, will raise Invalid_argument if called with an empty list. Right now, they return a promise that never resolves. See #562.

Happy concurrent programming!

Are there any OCaml podcasts out there?

Ozan Sener asked

Over the last two years OCaml has become my favorite language to program in. Decades of resources, open source projects, mailing list posts and IRC/Discord logs all helped me develop a taste for ML and build real things that were previously out of my comfort zone. Unfortunately, I'm currently not in a circle where I can tap into know-how of experienced OCaml developers, and I feel like I'm missing out.

I've been listening to https://reason.town/ lately, and I really like the casual format. Do you have anything similar, on any medium, that you are following?

Yawar Amin replied

I've never heard of an OCaml-specific podcast but I think sometimes OCamlers go on as guests in other podcasts. One that I enjoyed was @avsm on FLOSS Weekly talking about Mirage and OCaml https://twit.tv/shows/floss-weekly/episodes/302

Armael also replied

There was also a series of podcasts done during the December 2017 MirageOS hack retreat: https://discuss.ocaml.org/t/mirageos-audio-profiles-podcast-series/1482.

Other OCaml News

From the ocamlcore planet blog

Here are links from many OCaml blogs aggregated at OCaml Planet.


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