OCaml Weekly News

Hello

Here is the latest OCaml Weekly News, for the week of April 02 to 09, 2024.

moonpool 0.6

Archive: h= ttps://discuss.ocaml.org/t/ann-moonpool-0-6/14424/1

Simon Cruanes announced

Dearest friends of the dual hump,

I'm happy to announce the release of moonpool 0.6. Moonpool is a library of schedulers and concurrency primitives for OCaml 4.xx and 5.xx, based on thr= eads (possibly spread on multiple domains). Previous release announcements (0.5, 0.4, 0.3, 0.2, 0.1) contai= n more details.

This release is fairly large and contains some new libraries. The biggest i= mprovement is the addition of moonpool.fib (OCaml 5 only): it defines lightweight fibers with = structured concurrency, where the fibers can run on a thread pool chosen by= the user. Fibers also come with fiber-local storage and a notion of cancellation that= is propagated to children fibers. Overall, fibers are a nicer abstraction than bare futures (especially with monadic combinators). = There are currently no cooperative IO primitives provided by the scheduler but I have plans.

Another new, more experimental library is moonpool-lwt (OCaml = 5 only) which allows for interoperability between Lwt and moonpool: a moonpool future (or fiber) can be turned into a Lwt promise; and it becomes= possible to await a Lwt promise from moonpool, in a thread-safe way.

Docs:

sqids 0.1.0

Archive: ht= tps://discuss.ocaml.org/t/ann-sqids-0-1-0/14425/1

Leo Soares announced

I'm happy to announce the first release (0.1.0) of the official OCaml port of Sqids.

Sqids (pronounced "squids") is an open-source library that lets you generat= e short unique identifiers from numbers. These IDs are URL-safe, can encode several numbers, and do not contain common profanity w= ords.

https://opam.ocaml.org/pa= ckages/sqids

OCaml Retreat at Auroville, India (March 10th - March 15th)

Archive: https://discuss.ocaml.org/t/ocaml-retr= eat-at-auroville-india-march-10th-march-15th/14006/4

Sudha Parimala announced

I'm happy to share the experience report from the first OCaml Retreat: https:/= /ocamlretreat.org/2024/03/24/retreat-experience.html. Thanks to all the participants for contributing to the magic of the event. = We hope to run more such retreats in the future!

Miou, a simple scheduler for OCaml 5

Archive: https://discuss.ocaml.org/t/ann-miou-a-simple-schedu= ler-for-ocaml-5/12963/14

Calascibetta Romain announced

I am delighted to announce the release of miou.0.1.0. This rel= ease is undoubtedly the culmination and synthesis of the work of several individuals to offer a library that best fits our needs. We're quit= e convinced by the API we're proposing and quite happy with the implementation. As such, we're coming out of beta to offer version= 0.1.0. Above all, this means that the API will change very little, and the library is now ready for use. However, we are not yet = in 1.0.0 because we would like to give you time to use Miou, to observe possible bugs, and to give us time to correct these possib= le bugs in order to prepare version 1.0.0 with peace of mind. You can install the package via OPAM (it will be available soon):

$ opam install miou

We would sincerely like to thank all individuals who have contributed, whet= her directly or indirectly, to the project.

Furthermore, this new version of Miou builds upon the excellent work of @po= lytypic and his picos<= /a> project. We have incorporated certain elements that are suitable for implementing a schedule= r, and we hope that our efforts will lead to a certain standardization of the effects used by different schedulers in OCaml.

This rewrite has been carried out while trying to maintain the same semanti= cs and API as what we offered in version 0.0.1~beta2 (however, it is the nature of a beta to potentially break versions). This r= ewrite culminated in the reimplementation of an HTTP client and server (supporting http/1.1 or h2 with TLS which can handle 200k req/sec) as well as our good old happy-eyeballs= example. Moreover, the outcome of these implementations is more satisfying to us than their previous versi= ons. At least for now, considering the various changes our cooperative has embarked on=C2=B9, we will not yet release them.

We also took the time to integrate a version of the priority queue verified= using Why3. We would like to thank @= Armael and @backtracking (as well as the individuals who contributed to and maintained= the Vocal project) f= or their assistance.

Finally, I would like to personally thank the Robur cooperative for providing me with the necessary time to evolve= this project.

This release further confirms what we aim to offer to users, and in this re= gard, we have taken the time to write a small book explaining the use of Miou. This can also be seen as an introduction to asy= nchronous programming and effects. It is available here and is part of the = Miou distribution.

For any questions or assistance, we are available via email, this forum, or= Discord.

Happy hacking!

=C2=B9: As explained in this article, we try to replace Cstruct.= t by string and it requires obviously a deep change across severals packages.

OCaml.org Newsletter: March 2024

Archive: https://discuss.ocaml.org/t/ocaml-org-newsletter-march-2024/1= 4431/1

Sabine Schmaltz announced

Welcome to the March 2024 edition of the OCaml.org newsletter! This update = has been compiled by the OCaml.org team. You can find previous upda= tes on Discuss.

Our goal is to make OCaml.org the best resource for anyone who wants to get= started and be productive in OCaml. The OCaml.org newsletter provides an update on our progress towards that goal and an over= view of the changes we are working on.

We couldn't do it without all the amazing OCaml community members who help = us review, revise, and create better OCaml documentation. Your feedback enables us to better prioritise our work. Thank you!

This newsletter covers:

OCaml Cookbook: A prototype of an OCaml cookbook that provides s= hort code examples that solve practical problems using packages from the OC= aml ecosystem is on staging.ocaml.org/cookbook.
Dark Mode: We enabled the dark mode on all pages of OCaml.org, b= ased on your operating system / browser settings.
Community & Marketing Pages Rework: We are seeking feedback = on wireframes for the community section and for the marketing-related pages= .
General Improvements: As usual, we also worked on general mainte= nance and improvements based on user feedback, so we're highlighting some o= f our work below.

Open Issues for Contributors

You can find open issues for co= ntributors here!

Upcoming OCaml Cookbook

We're in the process of adding a community-driven section to the Learn area= : the OCaml Cookbook. This cookbook is designed as a collection of recipes, offering code samples for tackling real-world tasks = using packages from the OCaml ecosystem. It's a practical effort to enrich our learning resources, making them more applicable and us= eful for our community.

This month, our focus shifted towards finalizing the cookbook for release. = This includes

restructuring the directory structure and placement of recipe files, an= d
adding tasks to the cookbook, so that you can contribute recipes for th= ese tasks (we took inspiration from the excellent Rust Cookbook).

It will always be possible to propose more tasks for the OCaml Cookbook. Th= e main criteria here are:

task must require more than just a single Standard Library function cal= l to solve,
task must be focused on common problems that occur when trying to build= products,
if in doubt, make the task more specific, instead of more generic.

A good place to give feedback on the cookbook is this discuss thread.

Relevant PRs and Activities:

(WIP) Cookbook= compression / decompression by @F-Loyer
Cookbook : fix= in Lwt (type mismatch with iter_s/iter_p functions) by @F-Loyer
Update 00-caqt= i-ppx-rapper.ml - fix caqti-driver-sqlite -> caqti-driver-sqlite3 by= @F-Loyer

Dark Mode Released

We're happy to anounce that we shipped the Dark Mode for OCaml.org. Dark mo= de is activated based on your operating system / browser settings. If you see anything wrong, please open an issue and include the U= RL on which you're seeing a problem.

Relevant PRs and Activities:

Announce Dark Mode on Discuss
Add Preliminar= y Dark Mode for Package Documentation by @sabine
Fix: dark text= color on blue background by @amarachigoodness74
(dark mode) ad= just breadcrumbs text color by @sabine
(ui) Activate = Dark Mode by @sabine
Correctly inve= rt text on "Is OCaml Web" page by @SquidDev
fix: add missi= ng darkmode styles for in-package search results by @sabine
Remove legacy = tailwind colors and styles, tidy up darkmode colors by @sabine

Homepage & Marketing Pages Rework

The Home page project kicked off with an analysis of user surveys and inter= views, and the development of an initial wireframe for the homepage and the "Industrial Users" and "Academic Users" pages.

We've been reaching out to the community on Discuss and Twitter to find what people say about OCaml, so we can give a bit more cont= ext through testimonials on the "Academic Users" page.

Besides this, we've been asking on Twitter for ideas for the main tagline of the homepage

You can comment on the wireframes in Figma here.

If you have opinions on the homepage, feel free to share them in this discuss thread!

Community Section Rework

This week, we focused on creating wireframes for the Event, Job, Internship= , and Workshop pages, followed by soliciting feedback from the community via Discuss. Concurrently, work commenced on the UI design fo= r the Community Landing page, as well as the Event and Job pages.

We also made some improvements to the Events section on the Community page.= This involves better treatment of start/end times of events, as well as listing more upcoming events.

If you have opinions on the community section, feel free to share them in <= a href=3D"https://discuss.ocaml.org/t/looking-for-ideas-for-the-community-p= age-at-ocaml-org/14032/9">this discuss thread!

Relevant PRs and Activities:

Invite people to add events to events directory: https://discuss.ocaml.org/t/add-your-ocaml-events-to-the-community-pa= ge-on-ocaml-org/14251
Improve Events= Directory by @sabine
Fix template b= ug on upcoming events list by @sabine
Make clear upc= oming event time is UTC by @sabine
Data contributed to events:
- (data) Add S-R= EPLS event by @sabine
- (data) fix wro= ng date on event by @sabine
- (data) Add OCa= ml Retreat Auroville by @D8kTwoXfSUWLdpXruFrQiw
- (data) add OCa= ml Manila Meetup by @sabine

Outreachy Application Period & Internship

In March, OCaml.org hosted the application period for one Outreachy internship on creating an interactive experience for solving OCaml exercises.

The process of selecting an Outreachy intern involved creating and managing= 15 issues, reviewing 61 pull requests from 8 applicants. The tasks were similar in nature and dealt with restructuring the exercises= to enable an interactive experience, adding test cases and solutions (where missing).

Relevant PRs and Activities:

Create practic= e folder by @cuihtlauac
Sort exercises= by slug before emitting template by @csaltachin
Turning exercises into practice @Ozyugoo, @mnaibei, @divyankachaudhari,= @Kxrishx03, @maha-sachin, @MissJae, @jahielkomu, @Appleeyes

General Improvements and Data Additions

Relevant PRs and Activities:

(WIP) we're moving the OCaml Language Manual from v2.ocaml.org to ocaml= .org
set up dlvr.it to automatically post RSS feed items from OCaml Planet a= nd OCaml Changelog to new ocaml_org Twitter account
Link to recent= ly added videos on watch.ocaml.org by @sabine
Change twitter= account from OCamlLang to ocaml_org by @sabine
fix: small imp= rovements on news.eml by @sabine
is yet categor= y slug by @cuihtlauac
Add a badge fr= om the green web foundation to the carbon footprint page by @0xrotense<= /li>
Deployment of odoc 2.4.1 to package documentation pipeline:
- Compatibility = with odoc.2.4.1 by @gpetiot
- Patch for vood= oo / odoc 2.4.1 upgrade by @sabine
- chore: set doc= url to live, after voodoo upgrade by @sabine
Data:
- (data) add oca= ml.org newsletter February by @sabine
- Changelog entr= y for OCaml 4.14.2~rc1 by @Octachron
- Add dune.3.14.= 2 announcement by @Leonidas-from-XIV
- OCaml 4.14.2 r= elease and changelog pages by @Octachron
- OCaml 4.14.2: = fix release year by @edwintorok
- Add Platform c= hangelogs for February 2024 by @tmattio
- Changelog entr= y for OCaml 5.2.0~beta1 by @Octachron
- Add Outreachy = winter 2023 round by @patricoferris
Documentation:
- DOC: note abou= t windows ppx_show by @heathhenley
- (docs) Fix sma= ll typos by @kenranunderscore
- (docs) Add lin= k for instances of Array by @rmeis06
- Linking exerci= se to tutorials by @rmeis06
- Explain why t-= first works with labels by @mikhailazaryan
- Document that = begin … end use by @rmeis06
- Use uniform sy= ntax for eval steps by @cuihtlauac
- Linking mentio= ns of atomic module to doc by @rmeis06
- Linking Bigarr= ay references by @rmeis06
- (docs) fix exa= mple in 'Libraries With Dune' by @0xRamsi
- Fix typo in 4a= d_01_operators.md by @vog
- (docs) Use DkM= L 2.1.0 by @jonahbeckford

Opam 102: Pinning Packages, by OCamlPro

Archive: https://discuss.ocaml.org/t/blog-opam-102-pinning-= packages-by-ocamlpro/14437/1

OCamlPro announced

Greetings Cameleers,

Here=E2=80=99s another heads up for all opam users: Opam 102: Pinning Packages, our latest blog post breaking down opam for the community; as a keen eye would have already guessed, today's subject is pac= kage pinning!

We hope that this may be useful to anybody curious about getting acquainted= with opam's pins. This article is made for whom wonders how they work and when they are useful to be aware of.

Hoping that it may serve as a reference for all newcomers to the ecosystem.

We appreciate and are thankful for every reader, we welcome all your feedba= ck, right here, in this thread. :smile:=20

Kind regards, The OCamlPro Team

dune 3.15

Archive: http= s://discuss.ocaml.org/t/ann-dune-3-15/14438/1

Marek Kubica announced

We're happy to announce that Dune 3.15.0 is now available. This feature has= many fixes and new features that you can find in the changelog.

There are a few new features that we would like to specially highlight.

Removal of previous limitations in many forms

Prior to Dune 3.15 there were a number of limitations where percent forms l= ike %{env:...} could be used to expand to useful values. In this release, @rgrinberg put some effort to relax a lot of these restric= tions where possible.

In the new version some of these limitations have been lifted, so for examp= le {env:...} can be used in install stanzas (#10160).

Likewise there was no consistency where %{cma:...} or %{= cmo:...} could be used. With #10169, these form= s should work consistently everywhere.

Similarly the variables allowed in enabled_if fields have been= expanded in #10250, from just allowing variables that can be computed from the context to now allowi= ng all variables as long as expanding these variables does not introduce dependency cycles.

These relaxed rules can also be combined to enable a library depending on e= nvironment variables, e.g. (enabled_if %{env:ENABLE_LIBFOO=3Dfalse})).

Overlapping names in different contexts

Continuing the theme of conditionally enabling or disabling code to be buil= t, @jchavarri and @rgrinberg's work on #10220 makes it possible to have overlapping names between executable and melange.emit targets. This= can be useful when a name is to be shared in different contexts (e.g. one context with native compilation and one emitting code for the browser).

Properly output UTF-8 encoded text when formatting

Dune does not assume an encoding of dune files, however when files were for= matted the formatter would err on the safe side and escape bytes outside the ASCII range. This means that UTF-8 characters outside of = ASCII would get escaped into decimal escape sequences.

This was especially annoying in places where the user would write natural l= anguage texts, which is common when defining Opam packages in `dune-project` files. For example a discussion of a paper by = Paul Erd=C5=91s, Peter Frankl, Vojt=C4=9Bch R=C3=B6dl would upon reformatti= ng be turned into Paul Erd\\197\\145s, Peter Frankl, Vojt\\196\\155 R\\195\\182, = which does a disservice to these scientists and is hard to read.

Thanks to the work of @moyodiallo in #9728 starting with Dune 3.15 the original encoding will be preserved, so your package descriptions will be more readable.

Changelog

Added
- Add link flags to to ocamlmklib for ctypes stubs (#8784, @= frejsoya)
- Remove some unnecessary limitations in the expansions of percent forms = in install stanza. For example, the %{env:..} form can be used= to select files to be installed. (#10160, @rgrinberg)
- Allow artifact expansion percent forms (%{cma:..}, %= {cmo:..}, etc.) in more contexts. Previously, they would be randomly= forbidden in some fields. (#10169, @rgrinberg)
- Allow %{inline_tests} in more contexts (#10191, @rgrinberg= )
- Remove limitations on percent forms in the (enabled_if ..)= field of libraries (#10250, @rgrinberg)
- Support dialects in dune describe pp (#10283, @emillon)
- Allow defining executables or melange emit stanzas with the same name i= n the same folder under different contexts. (#10220, @rgrinberg, @jchavarri= )
Fixed
- coq: Delay Coq rule setup checks so OCaml-only packages can build in hy= brid Coq/OCaml projects when coqc is not present. Thanks to @v= zaliva for the test case and report (#9845, fixes #9818, @rgrinberg, @ejgal= lego)
- Fix conditional source selection with select on biga= rray in OCaml 5 (#10011, @moyodiallo)
- melange: fix inconsistency in virtual library implementation. Concrete = modules within a virtual library can now refer to its virtual modules too (= #10051, fixes #7104, @anmonteiro)
- melange: fix a bug that would cause stale import paths to = be emitted when moving source files within (include_subdirs ..) (#10286, fixes #9190, @anmonteiro)



Changed


Remove the --react-to-insignificant-changes option. (#1008=
3, @rgrinberg)



Ocsigen: summary of recent releases


Archive: https://discuss.ocaml.org/t/ocsigen-summary-of-recent-rele=
ases/13817/8



Vincent Balat announced


Eliom 10.4:


Basic client-server distillery template: sqlite is now the default back=
end
Basic template now has license unlicense
Basic template fixes
Compatibility with Tyxml >=3D 4.6.0 (by Vincent Laporte)



Ocsigen Start 6.3


Adding license Unlicense to the template
Dependecy to Tyxml >=3D 4.6





Js_of_ocaml 5.7


Archive: https://discuss.ocaml.org/t/ann-js-of-ocaml-5-7/14191/3



Hhugo announced


Js_of_ocaml 5.7.2 was released recently. It adds missing primitives require=
d by OCaml 5.2.0~beta





Eio Developer Meetings


Archive: https://discuss.ocaml.org/t/eio-developer-meetings/12207/5



Sudha Parimala announced


Following the release of Eio 1.0 (https://discuss.ocaml.org/t/ann-eio-1-=
0-first-major-release/14334), Eio goes into maintenance mode
for a bit. We've decided to pause the Eio developer meetings until further =
notice. Meanwhile, we remain active on the issue
tracker and the mat=
rix channel. I encourage
folks to try out Eio and report their findings.





Ocaml developer at Routine, Paris


Archive: https://discuss.ocaml.org/t/job-ocaml-developer-at-routi=
ne-paris/14448/1



mefyl announced


Routine (https://routine.co ) is once mo=
re looking for OCaml developers.



Routine is a personal productivity assistant and knowledge manager. The tec=
hnological stack revolves heavily around OCaml which
represents 80% of the codebase, both client and server side. The remaining =
20% are the UIs in various frontend framework:


Browser and desktop (Linux/Macos/Windows) through electron, using Js_of=
_ocaml (eyeing on WASM).
iOS via Swift bindings.
Android via JVM bindings (upcoming).



Our technological and academic background leads us to use designs that, I t=
hink, can pique the interest of seasoned Ocaml developer.
Amongst other things :



Type-driven programming based on ppx derivers that produces typescript =
declaration for frontend bindings, JSON schema to expose and consume extern=
al REST APIs (Google, Notion, =E2=80=A6), automatic SQL bindings, etc.
Automatic API and foreign binding generation for the different front en=
d technology, cross compilation.
Incremental  =
based state updates to refresh minimal subsets of the app.
Integrated graph query language to query and manipulate all the app dat=
a, including defining custom data types and workflows.
Highly concurrent implementation through Lwt and Eio - migrating to the=
 later as we go. Exception-free design. OCaml 5 with all the goodies.
Angstrom based parsing for the interactive console with highlighting an=
d completion.
Everything is very much library-oriented, with loads of reusable and sc=
affolded packages. Most of the work is intended to be open sources, or alre=
ady has been published.
An obsession for compile-time checks and type safety.



We use state of the art CI/CD and development processes. Salary is up to ma=
rket standard depending on the profile, plus usual options
package, to be discussed. We have a preference for presential work in our P=
aris 11th office (Charonne, 3 days a week) to help foster
team spirit but we won't pass on talented remote individuals.



We're looking to extend the team with talented and passionate engineers who=
 see the global picture and will work through all layers
of the project to see it succeed and create something we're proud of. While=
 we expect great OCaml and general computer science
proficiency, we=E2=80=99re open to most levels of experience. Thoroughness =
and a love for well rounded, robust and beautiful software design
is a must have - but that comes bundled with OCaml love, right ?



Do not hesitate to reach out for any question here, at [quentin.hocquet@rou=
tine.co](mailto:quentin.hocqu=
et@routine.co) or refer this
to someone who may be interested.



Thanks for your time and happy hacking !





dream-html 3.0.0


Archive: https://discuss.ocaml.org/t/ann-dream-html-3-0-0/14013/7



Yawar Amin announced


[ANN] dream-html 3.3.1



Add to_xml and pp_xml functions to render in XML =
style



Normally, dream-html defaults to rendering nodes in HTML style, meaning tha=
t void elements are rendered just like opening tags. Eg
<br>. With the new to_xml and pp_xml<=
/code> functions, we can now render nodes in XML style, meaning <b=
r />. This allows XML parsers
to successfully parse the output. So eg you can use dream-html to author an=
 ePub book.



Escape URI attributes like href with normal attribute escaping=
 rules in addition to percent-encoding. Most significantly,
ampersands are encoded now, eg /foo?a=3D1&b=3D2 is rendere=
d as /foo?a=3D1&amp;b=3D2.



Change where line breaks are inserted into the output markup, so that there=
 is no chance of injecting spurious whitespace into the
rendered page. This gives complete control over whitespace to the user.





Other OCaml News



From the ocaml.org blog


Here are links from many OCaml blogs aggregated at the ocaml.org blog.



Updates to OCaml.org's Learn Section: Enh=
ancing UI and UX





Old CWN


If you happen to miss a CWN, you can send me a message and I'll mail it to you, or go take a loo=
k at the archive or the <=
a href=3D"https://alan.petitepomme.net/cwn/cwn.rss">RSS feed of the archive=
s.



If you also wish to receive it every week by mail, you may subscribe to the=
 caml-list.




Alan Schmitt

OCaml Weekly News

Table of Contents

moonpool 0.6

Simon Cruanes announced

sqids 0.1.0

Leo Soares announced

Sudha Parimala announced

Miou, a simple scheduler for OCaml 5

Calascibetta Romain announced

OCaml.org Newsletter: March 2024

Sabine Schmaltz announced

Open Issues for Contributors

Upcoming OCaml Cookbook

Dark Mode Released

Homepage & Marketing Pages Rework

Community Section Rework

Outreachy Application Period & Internship

General Improvements and Data Additions

Opam 102: Pinning Packages, by OCamlPro

OCamlPro announced

dune 3.15

Marek Kubica announced

Removal of previous limitations in many forms

Overlapping names in different contexts

Changelog

Changed

Ocsigen: summary of recent releases

Vincent Balat announced

Js_of_ocaml 5.7

Hhugo announced

Eio Developer Meetings

Sudha Parimala announced

Ocaml developer at Routine, Paris

mefyl announced

dream-html 3.0.0

Yawar Amin announced

Other OCaml News

From the ocaml.org blog

Old CWN