chapel VS verona

Thanks, @subharmonicon!

While Chapel can run on many different systems, the main goal is making HPC programming much easier. Therefore, we are currently focusing on hardware that you can find in HPC systems (NVIDIA, AMD and Intel). Metal doesn't fall into that category, unfortunately. So far, the name came up infrequently in our discussions IIRC (especially targetting SPIRV), but we haven't heard from any [potential] user who may be interested in it. I would encourage you or anybody else interested in it to create an issue asking for the feature: https://github.com/chapel-lang/chapel/issues/new. Seeing public interest in that direction can change our prioritization.

One thing that I wanted to add that's not in the blogpost is the "cpu-as-device" mode. With that mode, you can use any machine, even one without a GPU, to write applications using Chapel's GPU features. That mode is for those who want to do initial development/debugging on their personal laptops before putting their application on an HPC system. In other words, while you can't use Metal directly, you can still write GPU-enabled applications in your Mac using Chapel, if the end goal is to run it on an HPC system. More details on cpu-as-device: https://chapel-lang.org/docs/main/technotes/gpu.html#cpu-as-...

Agreed. Here is a serious contender[0] minus all the hype and the $100M in VC money. You would expect a minimum of interest given how Mojo is received by the community, but not really in practice.

[0]: https://chapel-lang.org/

Cray is pushing their own language as well, Chapel.

https://chapel-lang.org/

As for Julia on Cray,

"Julia — The Newest Petaflop Family Language We Have Started to Love"

https://www.avenga.com/magazine/julia-programming-language

> Julia is one of the few languages that are in the so-called PetaFlop family; the other languages are C, C++ and Fortrant. It achieved 1.54 petaflops with 1.3 million threads on the Cray XC40 supercomputer.

https://chapel-lang.org if possible, Nix was also recently mentioned in Chapel Workshop https://chapel-lang.org/CHIUW2023.html https://github.com/twesterhout/nix-chapel

See Val for a possible step into that direction.

https://www.val-lang.dev/

Or how the Chapel language for HPC is going at it,

https://chapel-lang.org/

I suggest posting to a PLT focused resource, such as http://lambda-the-ultimate.org/

That said, a bit confused about the languages you reference in this context (Python, C#, JS) - didn't see any mention here or at your github repo of languages (some relatively ancient) in this space designed.

Sandia: Programming Languages for HPC [high performance computing] - is there life after MPI?

https://www.sandia.gov/app/uploads/sites/179/2022/04/SOS10-T...

Chapel:

https://chapel-lang.org/

https://en.wikipedia.org/wiki/Category:Array_programming_lan...

We needed the implicit conversion to `uint` in order for the overload resolution rules to make reasonable choices when faced with binary overloads for all of the numeric types. The document I linked talks through the examples. The case we were facing is something that we shared with `C#` -- in `C#` terms, if I make overloads for `f` for all numeric types (see https://github.com/chapel-lang/chapel/blob/main/test/types/coerce/allNumericsBinary.cs if you want to know exactly what I am talking about), then `f( myInt, myUlong )` runs `f(float, float)` which makes no sense. Especially if you care about numerical accuracy or program performance.

Code | Blog Walkthrough

According to this FAQ, snmalloc was designed for the Verona language:

https://microsoft.github.io/verona/faq.html

Unfortunately, I cannot find any significant code samples for Verona on the website or in the GitHub repo. There are a few types defined in a pretty low-level way:

https://github.com/microsoft/verona/tree/master/std/builtin

I think the future lies in figuring out how to get the benefits of that secret sauce, while mitigating or avoiding the downsides.

Like Boats said, the borrow checker works really well with data, but not so well with resources. I'd also add that it works well with data transformation, but struggles with abstraction, both the good and bad kind. It works well with tree-shaped data, but struggles with programs where the data has more intra-relationships.

So if we can design some paradigms that can harness Rust's borrow checker's benefits without its drawbacks, that could be pretty stellar. Some promising directions off the top of my head:

* Vale-style "region borrowing" [0] layered on top of a more flexible mutably-aliasing model, either involving single-threaded RC (like in Nim) generational references (like in Vale).

* Forty2 [1] or Verona [2] isolation, which let us choose between arenas and GC for isolated subgraphs. Combining that with some annotations could be a real home run. I think Cone [3] was going in this direction for a while.

* Val's simplified borrowing (mutable value semantics) combined with some form of mutable aliasing (this might sound familiar).

[0] https://verdagon.dev/blog/zero-cost-borrowing-regions-part-1... (am author)

[1] http://forty2.is/

[2] https://github.com/microsoft/verona

[3] https://cone.jondgoodwin.com/

Their approach lines up pretty well with how we do regions in Vale. [0]

Specifically, we consider the "spine" of a linked list to be in a separate "region" than the elements. This lets us freeze the spine, while keeping the elements mutable.

This mechanism is particularly promising because it likely means one can iterate over a collection with zero run-time overhead, without the normal restrictions of a more traditional Rust/Cyclone-like borrow checker. We'll know for sure when we finish part 3 (one-way isolation [1]); part 1 landed in the experimental branch only a few weeks ago.

The main difference between Vale and the paper's approach is that Vale doesn't assume that all elements are self-isolated fields, Vale allows references between elements and even references to the outside world. However, this does mean that Vale sometimes needs "region annotations", whereas the paper's system doesn't need any annotations at all, and that's a real strength of their method.

Other languages are experimenting with regions too, such as Forty2 [2] and Verona [3] though they're leaning more towards a garbage-collection-based approach.

Pretty exciting time for languages!

[0] https://verdagon.dev/blog/zero-cost-borrowing-regions-overvi...

[1] https://verdagon.dev/blog/zero-cost-borrowing-regions-part-3...

[2] http://forty2.is/

[3] https://github.com/microsoft/verona

Does this count? https://microsoft.github.io/verona/

What about new Rust that "Microsoft Research" trying to "explore" https://github.com/microsoft/verona/blob/master/docs/explore.md ?

Fun fact: the person who created Pony, Sylvan Clebsch, has been working on a Microsoft Research project called Verona. From it's README [0]:

> Project Verona is a research programming language to explore the concept of concurrent ownership. We are providing a new concurrency model that seamlessly integrates ownership.

https://github.com/microsoft/verona/tree/master