OCaml Weekly News

I managed to set up Emacs + TRAMP + LSP to do remote development (not on the first attempt though, as these things were quite fiddly to set up).

Here's what I got:

1. You need opam install ocaml-lsp-server on the remote machine.
2. Tell TRAMP to use path from the remote shell: (add-to-list 'tramp-remote-path 'tramp-own-remote-path)
3. Use Eglot as an LSP client. Although, lsp-mode claims that they support remote servers, I couldn't quite make it work with lsp-mode. This is what I have in my init.el:

(require 'eglot)
(add-hook 'tuareg-mode-hook #'eglot-ensure)

clangml.4.7.0 is now in opam, with the bug fixes/features requested by @n47 and some others. All LLVM/Clang versions up to 14.0.x are supported, as well as OCaml 5.0. The official repo is now on github: https://github.com/thierry-martinez/clangml which should ease posting issues and pull requests (and should be more convenient than discussions on this thread!).

Support for the upcoming Clang 15 is planned for the next release that should happen soon (the development version already supports Clang 15).

We are pleased to announce minor release of opam 2.1.3.

This opam release consists of backported fixes. You’ll find more information in the blog post.

To upgrade simply run:

bash -c "sh <(curl -fsSL https://raw.githubusercontent.com/ocaml/opam/master/shell/install.sh) --version 2.1.3"

Regarding Perl vs OCaml: An (impressive) implementation of all the solutions of the Perl Cookbook in the Objective CAML language (used at the time) is available here: http://pleac.sourceforge.net/pleac_ocaml/index.html

Re-writing these examples with "modern" code/libraries could be very interesting.

Is there a recommended way (or example) to build a simple binary distribution of an OCaml project using the GitHub CI? I am mostly interested in building the executables and packaging them in some archive format and make that available for download for different architectures.

I have such a workflow for one of my project, see this workflow file. It automatically triggers on new releases, builds the project with the appropriate compiler (e.g. flambda), and uploads the built artefact to the release page where it can be downloaded. It currently works for both linux and mac (last time I tried it with windows I got some errors and I haven't yet had the time to look into that, so i don't know if the errors were caused by the workflow, or my project).

That was a weird coincidence that I released a GitHub workflow https://discuss.ocaml.org/t/ann-setup-dkml-yml-github-actions-workflow-for-distributing-binaries/10308 for this today. @zozozo's solution is simpler if it works for your intended target audience.

I did the same for my little project bob but it provides a Cosmopolitan binary which should run anywhere, see the workflow and the last uploaded artifact :slight_smile:.

I am pleased to announce the `v0` release of `setup-dkml.yml`, a GitHub Actions workflow for distributing executables or libraries to the public:

• https://github.com/diskuv/dkml-workflows#readme

It is similar to the GitHub Action setup-ocaml but has several advantages when you are releasing a finished product to the public:

• On Linux it uses an ancient GLIBC (C library) so your binaries run on most Linux distributions without static linking. Statically linked binaries are simple to distribute, but can be problematic for some copy-left licenses, and makes it difficult for your end-users to do security patching of the libraries you linked with.
• On Windows it uses the Visual Studio compiler rather than the non-standard (for Windows) GCC compiler. This is a necessity when distributing Windows libraries, and reduces runtime bugs when linking native Windows libraries into your OCaml-built Windows executables. In addition you can generate Windows 32-bit binaries.
• On macOS it can build both ARM64 and x86_64 binaries if you use opam-monorepo to build your project. Alpha-release caution: This works today but only if you hand-edit the .locked file. So only advanced users today!

Even if you are not releasing to the public, if you are a package maintainer you may want to use both setup-ocaml and setup-dkml so that you get additional coverage for Visual Studio and MSYS2 on Windows, and coverage for an older GLIBC on Linux.

The full comparison matrix available at https://github.com/diskuv/dkml-workflows#readme is:

Put simply, use setup-dkml when you are distributing executables or libraries to the public. Use setup-ocaml for all other needs.

setup-dkml will setup the following OCaml build environments for you:

Thanks to the OCaml Software Foundation (OCSF) for their support of DKML. Enjoy!

Diskuv OCaml (DKML) has graduated to version 1.0.0. That means you'll see DKML listed as a Windows option for OCaml on the various OCaml websites soon.

To recap … by following the simple download and install instructions for Windows you will get:

• OCaml 4.12.1
• dune and opam working transparently as if you were on Unix
• a playground Opam switch so you can start coding without having to learn many Opam commands
• your Opam switches supported by the Visual Studio OCaml plugin
• all the prerequisites you need for OCaml programming:
  • a C compiler and assembler (Visual Studio Build Tools)
  • a UNIX environment (MSYS2; mostly you won't see it)
  • source control (Git for Windows)
• support! File an issue at https://github.com/diskuv/dkml-installer-ocaml/issues. I don't promise your Windows issue will be fixed, but it will be reviewed.

Changes since 0.4.0:

• An uninstaller. Now you can Add and Remove "Diskuv OCaml" from the Control Panel
• The old GitLab repository at https://gitlab.com/diskuv/diskuv-ocaml is being retired. There will be a new GitLab repository with much more testing capacity that will be online in the next few months.

Full documentation is at https://diskuv.gitlab.io/diskuv-ocaml/#introduction.

Package maintainers: Have a look at the just announced setup-dkml to test your own GitHub packages using most of the Windows functionality listed above.

Thanks (again!) to the OCaml Software Foundation (OCSF) for their support of DKML. Please consider becoming a contributor to DKML to improve the Windows ecosystem. Enjoy!