The Pre-Scheme Restoration

I believe the idea is essentially to write C semantics in scheme notation. Variables get marked with 'u32' or similar instead of being implicit sum types of anything the language can represent, memory allocation is explicit instead of garbage collected. In itself that essentially means writing C syntax trees in prefix notation, which is probably an acquired taste.

However scheme also comes with the compile time macro layer and that lot runs just fine in pre-scheme, garbage collected and all, because it's burned off before runtime anyway. Specifically, it's wholly macro-expanded before compilation to C (or similar), which is the obvious lowering to use for execution.

Also scheme has tooling, so if you're careful, the type annotated Cish syntax trees execute correctly as scheme, so you can debug the thing there, unit test it from scheme and so forth.

I really like it as a path to writing lisp runtimes in something that isn't C since an alarming fraction of them turn out to have a C runtime library at the bottom of the stack. Also for writing other things that I tend to write in C, where it's really the semantics I want and the syntax getting in the way.

But no more! It's so exciting that Andrew Whatson has begun reviving the project with such great enthusiasm and making it so that Pre-Scheme can run on top of a variety of Schemes. And it's wonderful that NLnet has recognized how important this effort is. I think Pre-Scheme could play an interesting role alongside Zed and Rust, and indeed I know that Andrew plans to incorporate many of the newer ideas explored in those languages on top of Pre-Scheme eventually.

Go Pre-Scheme revival... I'm cheering it on, and can't wait to use this stuff myself!

Pre-scheme: A Scheme dialect for systems programming (1997) [pdf] - https://news.ycombinator.com/item?id=29725313 - Dec 2021 (12 comments)

(surprised there hasn't been more)

The Nix/OS folks might take exception. I'm guessing this is tongue-in-cheek but it belies the tone of the rest of the post.

In all seriousness, though, this is exciting from a modern, end-user's vantage point and fascinating from an historical perspective.

Genuine question: would there be any advantages in targeting LLVM IR, rather than transpiling to C? With C being notoriously implementation dependent (down to things like the sizes of integer types), it seems like a messy target for something intended to be a sane systems language.

This is pretty cool, and it's generous of them to grant them funding, but (and I'm not trying to be rude) I wonder why they chose to give a grant for Pre-Scheme specifically. This seems only loosely related to the goals of the NGI Zero Core program (linked in the article):

"The next generation internet initiative envisions the information age will be an era that brings out the best in all of us. We want to enable human potential, mobility and creativity at the largest possible scale – while dealing responsibly with our natural resources. In order to preserve and expand the European way of life, the programme helps shape a value-centric, human and inclusive Internet for all."

...

"We want a more resilient, trustworthy and open internet. We want to empower end-users. Given the speed at which the 'twin transition' is taking place, we need a greener internet and more sustainable services sooner rather than later. Neither will happen at global scale without protocol evolution, which — as the case of three decades of IPv6 introduction demonstrates — is extremely challenging. NGI0 Core is designed to push beyond the status quo and create a virtuous cycle of innovation through free and open source software, libre hardware and open standards. If we want everyone to use and benefit from the internet to its full potential without holding back, the internet must be built on strong and transparent technologies that allow for permissionless innovation and are equally accessible to all."

I dream of some day soon running Emacs/Guix/Hurd on an open RISC-V chip and not having it be some flossy novelty but a genuine spiritual successor to Genera and the Lisp Machines.

Also when it comes to macros, does that include `syntax-rules` or `syntax-case` style macros, where the latter are much more powerful?

While an embedded Scheme-like language is incredibly useful, at some point I feel as if you would simply have to include these features, and to that end it would just be Scheme reinvented.