OCaml Weekly News

Hello

Here is the latest OCaml Weekly News, for the week of June 11 to 18, 2024.

Your opam-repository PRs are now tested on Windows

Archive: https://discuss.ocaml.org/t/ann-your-o= pam-repository-prs-are-now-tested-on-windows/14781/1

Kate announced

Following the merge of Windows support for the compiler in opam-repository and the= release= of opam 2.2.0~beta3, I'm happy to announce that a basic Windows CI usi= ng Github Actions is now in use in opam-repository, so all your new PRs are= now being tested on Windows too.

This is a big milestone, however the upstream opam-repository hasn't been t= ested with Windows before and thus many packages lacking the proper availab= ility metadata will fail to build in the next month or so. If you see a pac= kage that is definitely not going to be available on Windows, please do rep= ort it in the o= pam-repository bug-tracker or even better open a PR if you have the tim= e. When opening such PRs/issues, it would help the maintainers to copy/past= e the failing log in the PR description.

Most such PRs should simply add the following line to the failing package(s= ):

available: os !=3D "win32"

If you notice any issues in the Github Action itself or want to improve it,= please feel free to open a PRs/issue for that too, the code is available i= n opam-repository/.github/workflows/windows.yml.

Forester 4.1

Archive: h= ttps://discuss.ocaml.org/t/ann-forester-4-1/14800/1

Jon Sterling announced

I am pleased to announce the release of Forester 4.1 on opam, which is an OCaml utility to de= velop =E2=80=9CForests=E2=80=9D, which are densely interlinked mathematical= websites / Zettelk=C3=A4sten similar to the Stacks project or Kerodo= n . You can see the release notes on my own Fore= st.

There are a few new features, including a simplified command `forester init= ` to setup a fresh forest.

Thanks to Kento Okura, Nick Hu, and Trebor Huang for their contributions to= this release.

fun-sql 0.2.3

Archive: = https://discuss.ocaml.org/t/ann-fun-sql-0-2-3/14806/1

Yawar Amin announced

I am happy to announce the initial release of fun-sql, a simple functional-= style query library for SQLite and PostgreSQL.

To use it with SQLite: https://o= caml.org/p/fun-sqlite

To use it with PostgreSQL: h= ttps://ocaml.org/p/fun-postgresql

Fun-sql is not an ORM, it's a query execution and data mapping library (som= etimes called a micro-ORM). It does three things:

Create the prepared statement and encode the parameters
Execute the query
Decode the resultset into OCaml types using a set of combinators.

Here's an example:

open Fun_postgresql

module Note(Db : sig val db : Postgresql.connection end) =3D open Db

  type t =3D { id : int; txt : string }
  let ret =3D ret (fun row ->=
; { id =3D int 0 row; txt =3D text 1 row })

  (* Prepared statement: *)
  let edit =3D query db "update note set txt =3D $1 where id =3D $2"

  (* Use by simply calling it: *)
  let edit id =
txt =3D edit ~args:Arg.[int id; t=
ext txt] unit
  (* val edit : int -> string -> =
unit *)

  (* Prepared statement: *)
  let by_id =3D query db "select id, txt from note where id =3D $1"

  let by_id id=
 =3D only (by_id ~args:Arg.[int id] ret)
  (* val by_id : int -> t *)
end

The design enforces the use of prepared statements=E2=80=93indeed, with Pos= tgreSQL, a prepared statement corresponding to a query can be created only = once, so you have to ensure that you use a= pattern like the above.

MySQL support is also desired and I will get to it at some point unless som= eone beats me to it!

dream-html and pure-html 3.5.2

Archive: https://discuss.ocaml.org/t/ann-dream-html-pure-html-3-5-2/148= 08/1

Yawar Amin announced

Pleased to announce the release of dream-html 3.5.2, which actually spawns = a new package pure-html: https://= ocaml.org/p/pure-html

This package offers the same functionality as dream-html, except without a Dream dependency, so you can use whatever = web server you like, or even use it for other applications than web servers= . It works exactly the same way as dream-html, except the top-level module = is Pure_html:

open Pure_html
open HTML

let content =3D article [] [
  p [] [t=
xt "Header"];
  p [] [t=
xt "Body"];
]

pure-html has a runtime dependency only on the uri package.

Control Structures, English translation of lectures by Xavier = Leroy

Archive: https://discuss.ocaml.org/= t/control-structures-english-translation-of-lectures-by-xavier-leroy/14810/= 1

unfode announced

Website.

Really learned a lot from the slides. For example, the most understandable = definition of continuation I've ever seen:

Given a control point in a program, its continuation is the sequence of com= putations that remain to be done once the execution reaches the given contr= ol point in order to finish the execution of the whole program.

Ppxlib dev meetings

Archive: https://discuss.ocaml.org/t/ppxlib-dev-meetings/12441/24

Nathan Rebours announced

This month's meeting is scheduled today, Tuesday June 18th, at 6:00PM CET.

Sorry for posting the announcement so late!

Here is the meeting agenda:

5.2 AST bump
Driver Transform refactoring
5.3 support
- Added a trunk CI build, we should be able to consider merging
- Still need documentation for releases
Driver anti-warning 34 code gen
- Still haven't heard from Janestreet, we need their feedback before movi= ng forward with this
Ocamlfind support
- There seem to be a bug when a ppxlib based ppx is invoked directly usin= g ocamlfind -package
- Is this something we want to actively maintain
Dune w/ ppx
- Nathan got back to it, hopefully it should be ready soon
Repo hygiene: issue triage
- We have a lot of issues, most of which are extremely old
- A lot of issues are actually questions on how to use ppxlib for ppx aut= hors
- It's worth having a go at closing the irrelevant issues and have some c= lassification system for the rest

The meeting will be hosted on google meet here: https://meet.google.com/yxw-ejnu-cju

You are welcome to join!

Other OCaml News

From the ocaml.org blog

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

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

Your opam-repository PRs are now tested on Windows

Kate announced

Forester 4.1

Jon Sterling announced

fun-sql 0.2.3

Yawar Amin announced

dream-html and pure-html 3.5.2

Yawar Amin announced

Control Structures, English translation of lectures by Xavier = Leroy

unfode announced

Ppxlib dev meetings

Nathan Rebours announced

Other OCaml News

From the ocaml.org blog

Old CWN