OCaml Weekly News

We are happy to invite submissions to the ML Family Workshop 2022, to be held during the ICFP conference week on Thursday, September 15th.

The ML family workshop warmly welcomes submission touching on the programming languages traditionally seen as part of the “ML family” (Standard ML, OCaml, F#, CakeML, SML#, Manticore, MetaOCaml, etc.). The scope of the workshop includes all aspects of the design, semantics, theory, application, implementation, and teaching of the members of the ML family. We also encourage presentations from related languages (such as Haskell, Scala, Rust, Nemerle, Links, Koka, F*, Eff, ATS, etc), to exchange experience of further developing ML ideas.

The workshop does not have proceedings, making it the perfect venue to run some ideas with the community or present some work in progress within a friendly environment. The PC has a broad expertise and submissions are 3 pages long: when in doubt, just submit!

Currently, the workshop is scheduled to be an in-person event. We will give to the authors of accepted abstracts the opportunity to give their talks remotely if necessary, in case they could not travel.

See the detailed CFP online on the ICFP website: https://icfp22.sigplan.org/home/mlfamilyworkshop-2022#Call-for-Presentations

On behalf of the dune team, I'm pleased to announce the availability of version 3.2.0. This release contains few new features, but is packed with bug fixes and usability improvements. In particular, I'd like to point out that we've continued to improve the user experience with the watch mode. I encourage you all to try it out if you haven't already.

Happy Hacking.

Hi everyone! Last fall, we completed our original plan for this project, rewriting the verilog MIPS CPU we had designed for a class into Hardcaml. A few weeks later, we got an invite to video-meet with the Hardcaml team to talk about our experience. They even sent us actual Arty A-7 FPGAs so we could test out our simulation on real hardware!

Junior year ended up much busier than expected, and although we had gotten our code onto the FPGAs by January, we’ve only just now fully finished our project. Our blog now has 2 bonus installments:

1. Running Hardcaml on an actual FPGA. Here, we lit up LEDs to display the output of a hardcoded program.
2. Hardcaml MIPS and I/O. Here, we restructured our CPU so that programs can communicate with an external device using UART.

With these changes, our full design is now a simplified but realistic processor that can run meaningful programs.

Thank you very much to @andyman, @fyquah95, Ben Devlin, and the rest of the Jane Street FPGA team for creating Hardcaml, meeting with us, and answering our numerous questions throughout this process. Thank you also to @yaron_minsky and Jane Street for sending us the FPGAs to try out our code.

This has been an incredibly interesting, challenging, and rewarding journey. We hope that our blog posts and sample project are useful for learning Hardcaml in the future, and welcome any questions or comments.

I ran a hands-on tutorial on the new parallel programming primitives in the upcoming OCaml 5 at the Tarides off-site last week. It covers the low-level parallelism primitives exposed by the OCaml 5 compiler as well as high-level parallel programming using domainslib. I hope you like it and find it useful. Please feel free to open issues if you find anything amiss.

https://github.com/kayceesrk/ocaml5-tutorial

As it is not immediately clear for me, does it uses threads , green threads, processes , fibers ? And who is responsible for the scheduling ,the Ocaml application or the underlying operating system ?

Each domain corresponds to one system thread. The scheduling between them is therefore performed by the operating system.

The tutorial only covers domains, which are the way to perform parallelism in OCaml 5. To use concurrency (e.g. having several IO-depending operations that run concurrently on the same core), the main mechanism is effects (which at the level of the runtime system, are implemented using small stack segments called fibers), as in the eio library. Effects allow such libraries to provide a form a lightweight threads (aka green threads) whose scheduling is implemented in the OCaml application using effect mechanisms.

Here is a very simple tutorial on parallel programming in OCaml: use parany ! https://github.com/UnixJunkie/parany For OCaml 5, use the right branch of parany: https://github.com/UnixJunkie/parany/tree/domains

Happy hacking!