OCaml Weekly News

Following the release of json-data-encoding.0.9, I am happy to announce the release of ppx_deriving_encoding.0.2.2.

The code source and some documentation is available on gitlab, and the package can be installed with opam (opam install ppx_deriving_encoding).

This ppx allows to derive encoding of json-data-encoding library from most of ocaml types.

Have fun!

The release of OCaml 4.12.0 is on the horizon. We have created a new beta version to help you adapt your software to the new features ahead of the release.

Compared to the first beta release, this new release contains one fix for the Thread library (for a race condition on Windows), and experimentally re-enables building the compiler on illumos and Oracle Solaris.

We are expecting this beta to be the last one before the release.

If you find any bugs, please report them here: https://github.com/ocaml/ocaml/issues

Happy hacking,

– Florian Angeletti for the OCaml team.

And there is XMPP: <xmpp:ocaml@conference.orbitalfox.eu?join>

I am happy to announce first release of Timere, a time handling and reasoning library, which @Drup and I have been working on recently.

Not primarily a programming article but I thought this is an interesting exception because it may be the first time OCaml has been mentioned in the Financial Times: https://www.ft.com/content/81811f27-4a8f-4941-99b3-2762cae76542

On behalf of Nomadic Labs, it is my pleasure to release json-data-encoding.0.9.1. The code of this packaging-fix release is identical to the recent json-data-encoding.0.9 but the license information has been corrected.

The previous release had LGPL with linking exception headers in the source files, LICENSE file in the repository, and license field in the opam file. However, the code was actually under MIT as per agreement of the copyright holders. Release 0.9.1 has the correct license headers, LICENSE file and license field in the opam files.

The code of 0.9/0.9.1 is in dual license. Future releases will be under MIT license only.

I'm pleased to annonce that ocamlearlybird 1.0.0~beta1 just released. Will soon be available on opam.

This is a big step that we toward 1.0.0. We solved lots of issues and tested with realy ocaml projects such as utop, ocamlformat, and so on. And certainly, it can debug ocamlearlybird itself.

Try yourself!

Since the post has edited over 3 times. I can't edit it anyway. I uploaded demo video here:

Debug utop

As a follow-up to an earlier conversation, I made a cheatsheet and a template for using cmdliner by @dbuenzli. It was done quickly and I don't know everything about cmdliner, so please let me know if you see mistakes.

Good to see this. I believe a common use case is to add are sub commands as popularised by git. It looks like this in my code:

module C = Cmdliner

let report =
  let doc = "generate HTML or JSON report for an outing" in
  let man = ..   in
  C.Term.
    (ret (const make $ common_options $ json $ path), info "report" ~doc ~man)

let default =
  let help = `Help (`Pager, None) in
  let doc = "GPS analysis for rowers" in
 C.Term.(ret @@ const help, info "eightplus" ~doc ~man)

let cmds = [ export; report; topspeed; debug; summary; help ]
let main () = C.Term.(eval_choice default cmds |> exit)
let () = if !Sys.interactive then () else main ()

I just added a demo/template for subcommand handling. There are now two demo programs. One is focused on the different kinds of arguments and the other one on subcommands.

In this same vein, I've been compiling "executable notes" whenever I find myself needing a certain Cmdlner recipe. I took took these recent discussion as an occasion to document the module a bit: https://github.com/shonfeder/kwdcmd

The aim is to provide "self-documenting" constructors that encode the composition of common CLI terms into module namespaces, labeled args, and type aliases. The hope being that I can have the type signature of a combinator give me all the hints I need to avoid having to look up the documentation every time :laughing:

It's just a very rough (and quite imperfect) collection of idioms I've found useful, but it could be worth a look! When i get a chance, I hope to look through your cheat sheet to make sure I have a representative constructor for each idiom you've documented.

I'm happy to announce that containers 3.2 has just been released. It should arrive on opam soon. It notably contains an Either compatibility wrapper, more formatting functions, list functions, and a bunch of fixes. Many thanks to @darrenldl for contributing some initial fuzzing support.

Join us with your questions about the OCaml language, or just to hang out with the OCaml community. Especially geared toward new and intermediate users, experienced OCaml developers will be available to answer your questions about the language and ecosystem.

Whether you’re still trying to make sense of currying or can spot non-tail-recursive code from across the room, we hope that you’ll join us on Thursday, February 11 at 7pm (U.S. Central time). Meeting info and additional details can be found at https://hfpug.org.

You may be interested in cmgraph which scrapes the compiled modules (*.cmi/*.cmo/*.cmx) instead of the source code. It needs no compilation switch options since it does not scrape source code.

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

• Recent and upcoming changes to Merlin
• The road ahead for MirageOS in 2021
• Release of Alt-Ergo 2.4.0