6 ms·

Rewriting Rust: A Response

140 points by gavinhoward 2y ago

az09mugen 2y ago
Wow, about Yao: "In fact, it might be better said that Yao is meant to be: As powerful as C, As flexible as Lisp, As easy as Python, As provable as Ada/SPARK, More reliable than Rust, With the time semantics of HAL/S." Even if I don't really believe in this incredible statement, I'm really curious to see what can be the result.
- gavinhoward 2y ago
  Author here. Yeah, you shouldn't believe it yet, but here is the status of each: * "As powerful as C": unproven. I might need something like Rust's `unsafe`, and even though I have something in mind for that, it requires that any program be expressible in Dynamic Restricted Structured Concurrency, an open problem. I am working on a proof, though. * "As flexible as Lisp": I think this is proven. Yao has equivalents for both macros (keywords) and reader macros (lexing modes). My build system uses its own keywords to implement a build DSL [1]. The shell sublanguage uses a lexing mode, and another makes it possible to embed JSON. * "As easy as Python": in retrospect, this isn't quite possible, but I hope to get 90% of the way. * "As provable as Ada/SPARK": I'll let you read the design in [2] and decide for yourself. But Yao will also have contracts. * "More reliable than Rust": unproven, but I think the lack of async will go a long way. * "With the time semantics of HAL/S": unproven. HAL/S was what the Shuttle software was written in [3]. It was hard real-time. Because Yao will be distributed in IR form [4], the back end could leverage knowledge of worst-case instruction latencies to calculate worst-case response times. This same thing will also allow using only constant-time instructions for cryptography, using a `constant_time` function trait. [1]: https://rigbuild.dev/build.rig5/#keywords https://rigbuild.dev/build.rig5/#keywords [2]: https://gavinhoward.com/2024/05/what-rust-got-wrong-on-formal-verification/ https://gavinhoward.com/2024/05/what-rust-got-wrong-on-forma... [3]: https://www.fastcompany.com/28121/they-write-right-stuff https://www.fastcompany.com/28121/they-write-right-stuff [4]: https://gavinhoward.com/2024/09/rewriting-rust-a-response/#distribution https://gavinhoward.com/2024/09/rewriting-rust-a-response/#d...
  - az09mugen 2y ago
    Thank you very much for your detailed answer. Will look into your links right now.
  - az09mugen 2y ago
    Hats off, you really did in fact a deep analysis of Rust conceptual errors by searching alternative ways to fix Rust async. Also by understanding and describing the decisions you made and what are their architectural implications (I liked the good, the bad and the ugly part). While I can't appreciate the entirety of this language because I can't grasp all the technical subtilities, I really like the core ideas at the basis of Yao and the spirit you put into it. I hope I can play with this language some day. And wish you good luck with this nice project.
    - gavinhoward 2y ago
      This is one of the nicest, yet honest, compliments I have ever received. Thank you!
  - AlotOfReading 2y ago
    Worst case execution times are generally unknowable, even at codegen. It depends on things like the specific microarchitectural details, what other instructions are currently executing, the memory hierarchy, what instructions have been executed before, how the power supply is responding, what the thermal environment is like, etc. HAL/S dealt with these problems by a combination of programmer/validation discipline, custom hardware designed for hard real-time usecases, and generous support from the underlying RTOS (FCOS). Cryptography code doesn't deal with it, it just avoids data dependent nondeterminism, which is good enough for those use cases.
    - gavinhoward 2y ago
      Yes, you are correct. My idea is to cause a compile error if the backend can't use all instructions for which it knows the worst case latency or if it can't use purely constant-time instructions.
ubj 2y ago
Interesting response. I'm as curious as anyone else as to how Yao will improve upon Rust, but here is what I've observed from following several (relatively) recently created languages (Julia, Nim, Mojo, JAX): * Language creators start with high hopes and big promises. "We've learned from the past! This will solve all the problems of previous X,Y,Z languages! It will be so much easier to use!" * The language begins to be designed, implemented, and developed. Problems arise. Tradeoffs must be made. Invariably, the new language develops its own set of limitations, shortcomings, and weaknesses. These are inevitable with any new programming language. * Ultimately the language either finds a userbase who are willing to overlook or work around the limitations and pitfalls, or it fades away. * If it remains, eventually another new language arises saying "We've learned from the past! This will solve all the problems of previous X,Y,Z languages! It will be so much easier to use!" And the cycle repeats. Now, is this a bad thing? I would argue no, not necessarily. Every time a new language is created, our vision of what is possible is expanded. We learn new lessons about what works and what doesn't work in programming languages. So in short I'm looking forward to see how the state of the art is advanced by Yao. If it gets to a decent working state, I might even try it out if I have time. However, in light of the above statements forgive me for being skeptical of the following claim from Yao's website [1]: > As powerful as C, As flexible as Lisp, As easy as Python, As provable as Ada/SPARK, More reliable than Rust, With the time semantics of HAL/S. [1]: https://git.yzena.com/Yzena/Yc/src/branch/master/docs/yao/main.md https://git.yzena.com/Yzena/Yc/src/branch/master/docs/yao/ma...
- gavinhoward 2y ago
  Author here. You are absolutely right to be skeptical. I wrote that a long time ago. I did detail the current status of those claims in a comment: https://news.ycombinator.com/item?id=41672316 https://news.ycombinator.com/item?id=41672316 .
- jadbox 2y ago
  Fwiw, Zig is one of the few languages on my radar that's on the uptick. At least in my circle, I know people from firmware to VM development that moved from Rust over to Zig for its flexibility. There' also Bun that managed to nearly be a drop-in replacement for Node in a very short development cycle, which they claim is due to Zig. (I am not associated with Zig nor have a lot of experience with it yet)
steveklabnik 2y ago
I am always glad to see people pursuing creating their own programming language. More people should give it a try, IMHO. A tricky thing that comes up with Rust comparisons is that often, Rust has a feature that's weird or hard to use, but it's because that's the only solution that makes sense within the constraints Rust has placed upon itself. Clicking some links gets me to https://git.yzena.com/Yzena/Yc/src/branch/master/docs/yao/design.md https://git.yzena.com/Yzena/Yc/src/branch/master/docs/yao/de... > Yao's biggest goals are: Correctness, Convenience, Performance, in that order. Having clear goals is a great thing when making a language, because they give you guidance on what is appropriate to include and what is not. Rust has certainly demonstrated having similar goals, but in a slightly different order: Correctness, Performance, and then Convenience. So it wouldn't shock me if Yao could do some things better than Rust, in accordance with its goals. But that also means that sometimes, Rust would be useful where Yao cannot be. Everything is tradeoffs. Incidentally, I actually think that figuring out what your values are, and what your needs are, is a great way to pick a programming language. Decide what matters to you as an engineer, and then find a language that shares similar values. I gave a conference talk a few years back on this idea, and how I viewed Rust's values at the time https://www.infoq.com/presentations/rust-tradeoffs/ https://www.infoq.com/presentations/rust-tradeoffs/ This was based off of bcantrill's Platform as a Reflection of Values, which was very influential on me. https://www.youtube.com/watch?v=Xhx970_JKX4 https://www.youtube.com/watch?v=Xhx970_JKX4 If you've ever heard about Oxide's focus on values, this is some of the older background on that.
- gavinhoward 2y ago
  I wish I could upvote you twice. I decided on my values because of bcantrill's talk. Everyone should watch it. A more complete list of my values is at https://git.yzena.com/Yzena/Yc/src/branch/master/docs/adl/0000-values.md https://git.yzena.com/Yzena/Yc/src/branch/master/docs/adl/00... .
  - andai 2y ago
    Could you elaborate on value #0 being users (and what it means to prioritize users over programmers)?
sgt 2y ago
Glad I waited before starting with Rust. Now I can just jump straight to Yao. Rust is so early 2020s.
- bregma 2y ago
  You're still using Yao? Pfff.
  - chipdart 2y ago
    > You're still using Yao? Pfff. One-up flex master right here. Unbeatable.
    - sgt 2y ago
      Hip crowd's already moved on to Tcl, I know (with the advancements in v9.0 and all).
      - Ygg2 2y ago
        Tcl is yesterday's news. Hip crowd moved to artisanal ASM.
        falcor84 2y ago
        Excuse me, but real programmers use butterflies https://xkcd.com/378/ https://xkcd.com/378/
  - epage 2y ago
    > Pfff Now I want a language named that.
- gavinhoward 2y ago
  Please don't jump to Yao! The only thing it's good for right now is to replace shell scripts.
wizzwizz4 2y ago
> Instead of marking asynchronous functions, languages should have had us mark synchronous functions […] Although that wouldn’t remove the possibility of bugs when calling a blocking function in async code, So mark "synchronous" (i.e., non-yielding) and "asynchronous" (i.e., non-blocking). Then we can have the synchronous colour, the asynchronous colour, functions that are both (e.g. pure CPU-bound tasks, like arithmetic), and functions that are neither (e.g. buggy code).
Animats 2y ago
Mostly an ad for Yao. - Is there really a major use case for function traits? Is more elaboration of the type system actually useful? - The original "Rewriting Rust" article discussed replacing Rust's macro system. That's not mentioned here. If you had to write your macros in Rust, to be run in compile time, would that be a win? I doubt it. Each macro would start with a call to a parser, and then you generate code as strings. This would pay off only for complex cases such as a regular expression compiler. Rust already has compile-time build programs, where you can run Rust during the build process. (I use that to take in an API definition from another source and generate Rust.) - "Runtime capabilities" seems to be an attempt to build a container system into the language. It's not clear that helps much. That's really the OS's job. Protecting programs against themselves is nice, but not usually the problem. I'd like to see something in Android that gives an app file access with less access than "all files". Like "Can read what was installed for this app, can write working subdirectory for this app, and nothing else."
- gavinhoward 2y ago
  Fair criticisms, John. I just want to address macros. Yao has something like Rust's macros. They are called "keywords," because even the built-in keywords are implemented that way. (That is why Yao can just not have a `while` keyword.) My Yao-based build system, Rig, uses keywords to implement a build DSL. [1] And keywords are fast to compile. [1]: https://rigbuild.dev/build.rig5/#keywords https://rigbuild.dev/build.rig5/#keywords
- nicoburns 2y ago
  > Is there really a major use case for function traits? Absolutely. They can be used for function overloading, and for manually creating closures from structs, which can be more ergonomic sometimes. Whether you want those features is another matter. The rust compiler supports them but doesn't expose them to stable rust.
- ruthmarx 2y ago
  > 'd like to see something in Android that gives an app file access with less access than "all files". SELinux has been able to solve that problem in Android for a long, long time now. Which is more appropriate, as you say it should be the job of the OS. The problem is the age old one where users want convenience at the cost of security.
osigurdson 2y ago
Without sounding too much like a Cathy Woods, I'm wondering if AI can be leveraged to help with all of the non-core aspects of creating new languages? For example, really why does every language really need a json parser, or http requests library. If one were to examine the machine code instructions involved in each, they would likely be rather similar after all. Writing all of that stuff is an enormous lift for the community. Tooling is similarly "undifferentiated heavy lifting" in a way. Also, moving existing code bases to new languages is still hard. If there were better ways to achieve these things, there would be much less inertia in the language space.
tazjin 2y ago
Odd post, and it landed me on the Yzena website which is very surreal. It seems to be intentionally hard from the website to figure out what Yzena is or why anyone would want to buy a license for it (or the things it makes?). There was a link to a repo full of perl scripts, though. According to the website I'm not allowed to ask about this though ;)
- gavinhoward 2y ago
  I only have one Perl script in that repo... Anyway, Yzena is my business. I am not a very good marketer, and the website is bad. I also don't think I will get any business, but eh.
dang 2y ago
Recent and related: Rewriting Rust - https://news.ycombinator.com/item?id=41654871 https://news.ycombinator.com/item?id=41654871 - Sept 2024 (385 comments)
andai 2y ago
>Yao can’t be compiled in the traditional way. >Instead, Yao will be compiled to an LLVM-like IR (which already exists), and that’s how it will be distributed. Users will have to do the final compile step on their local machines. Is this referring to the compiler itself, or programs written in Yao?
- gavinhoward 2y ago
  Programs written in Yao.
  - kibwen 2y ago
    If the goal is portability, Google pursued the idea of distributing cross-platform LLVM IR via PNaCl and ultimately abandoned it, because LLVM IR isn't really designed for portability.
    - gavinhoward 2y ago
      I designed my own, uncreatively called Yvm. Yao already compiles to it.
andai 2y ago
Is there something like this but without concurrency? I don't need concurrency or multithreading, and most of my pain with Rust has come from the fact that it prevents me from doing things that I know are correct because it thinks my code will run in a multithreaded environment (it will not). It seems like Yao's whole project is solving the concurrency problem. I'm like, why not drop it entirely (if performance isn't one of the language's top priorities anyway)? What does keeping it gain that's so important? (Context: I don't understand concurrency and multithreading.)
- gavinhoward 2y ago
  Good question. Yao's concurrency will be explicit. You will not get concurrency unless you open a threadset and spawn threads. Yao scripts run in a single thread by default. I focused on solving the concurrency problem because if it is solved, single thread code is solved as well.
- skitter 2y ago
  > it prevents me from doing things that I know are correct because it thinks my code will run in a multithreaded environment Could you elaborate on that? In your case you don't need to worry about Send/Sync, you can use Cell/RefCell, etc. The borrow checker isn't about threading, it's useful in a purely single-threaded context too.
  - School-Cotton 2y ago
    Not OP but don’t a lot of async libraries require things to be Send because they assume they’ll run on a multithreaded executor?
- ruthmarx 2y ago
  > I don't need concurrency or multithreading, > ... > Context: I don't understand concurrency and multithreading. I get not needing it, but if you don't understand concurrency or multithreading how are you so certain you don't need concurrency or multithreading?
- klabb3 2y ago
j1elo 2y ago
> that language is coming into existence right now! It is called Yao. Wasn't it called Mojo? It's been a while since I saw traction of that new language over here. Anyhow, it is interesting how many new languages are appearing every day. The bar is indeed constantly moving upwards.
- mepian 2y ago
  Mojo is completely unrelated, created by Chris Lattner and his team at Modular AI.
  - deleted 2y ago
    [deleted]
cryptonector 2y ago
> This is actually the root of the function color problem: async is exactly backwards! Instead of marking asynchronous functions, languages should have had us mark synchronous functions, and then async should have been the default! What happens when you need to add a new trait that all existing functions must be changed to have? That's why async is generally an attribute. The answer is that we'd have to say that all functions have some default trait set that can be extended automatically as the language evolves, except those anti-traits they have. Then we could say that a function is async meaning "not sync", or even we could write !sync instead of async. I rather like the idea that you have to write `!sync` instead of `async`.
- gavinhoward 2y ago
  The post answers that. Every unmarked function can do anything. If you add a new thing that functions can do, you assume unmarked functions can do it (even if they don't), and you add a trait for the negative.
  - cryptonector 2y ago
    Thanks, I got interrupted in my reading.
klabb3 2y ago
> The Rust async book mentions three more methods: […] Hah, I wrote this section and was deeply aware of these problems at the time. Let’s just say it didn’t fit in the introduction. In fact, a lot of the understanding of this issue has been expressed later, blog post by blog post, largely without coordination. It’s almost eerie to see again and again people encountering the same issue, and spending huge effort to address it (this one takes the prize though - making your own language). Let me try a to narrativize it: we have a fundamental problem with unrestricted concurrent control flow (very similar to how we used to have unrestricted sequential control flow when we had goto). This problem exists in most programming languages, but we mostly pretend it’s not there (and live with the subtle bugs instead). However, with Rust’s unique ownership- and safety model, the lack of structured concurrency was an unavoidable problem, at collision course with Rust itself. In the Rust we have today (without structured concurrency), a bunch of expected and reasonable behaviors cannot be achieved (such as borrowing from a parent task).
- throwaway17_17 2y ago
  Do you know of any longer form content that walks through this area, or maybe just a listing of blogs. I have a feeling the resources are relatively scattered over various sites and across time, so any tips on search terms to use if a deep dive into this problem (both in Rust and generically in programming language semantics) intrigues me?
  - genter 2y ago
    https://vorpus.org/blog/notes-on-structured-concurrency-or-go-statement-considered-harmful/ https://vorpus.org/blog/notes-on-structured-concurrency-or-g... https://dubroy.com/blog/handling-user-input-with-structured-concurrency/ https://dubroy.com/blog/handling-user-input-with-structured-... The first one is particularly good. Both of those have links to more topics.
  - klabb3 2y ago
    Sibling already gave great pointers to structured concurrency in general. For rust specifically the links in the post were good, some I hadn’t seen that came up in the last 2 years. Perhaps someone from deep PL background has more rigorous papers and such to point to? I highly doubt this is being discovered now for the first time – it wouldn’t surprise me if there’s a whole academic sub-branch about similar things. Given how important concurrency is, and how difficult it is to get right, there’s a lot of opportunity for academia to tackle the problem space. We sure as hell need it.
divs1210 2y ago
This discussion is seriously lacking in references to Koka language[0]. Koka is memory safe without using traditional GC, has effects, and is pretty cool over all. [0] https://koka-lang.github.io/koka/doc/index.html https://koka-lang.github.io/koka/doc/index.html
- SkiFire13 2y ago
  Reference counting is ultimately a GC, although not a tracing GC which is the most common kind. I also don't really see the appeal of not having a GC in a language like that. If it doesn't compete with C/C++ for performance and low level support then not having a GC is no longer an advantage. That said Koka still remains very cool for the effect system though, and I would really like to see it in a mainstream language!
tmtvl 2y ago
Serious mode: it's good that people are exploring the programming language space, both tiny and big changes can mean a world of difference in reducing bugs and making programs nicer both for the user to run and the developer to create and maintain. Serious mode off. When will we get Yao in the Linux kernel?
- gavinhoward 2y ago
  > Serious mode off. When will we get Yao in the Linux kernel? As soon as someone pays me long enough to get it there. :) I only have 3 hours max a day (usually only 2) to work on Yao. And I have other projects I want to do as well. But if someone paid, I sure could find the desire to work on it.
- fuzztester 2y ago
  >Serious mode off. When will we get Yao in the Linux kernel? Yaol can get involved and help with that, yaol know? Serious_mode_still_off? true
cryptonector 2y ago
Slightly off-topic, but TFA links to https://gavinhoward.com/2024/05/what-rust-got-wrong-on-formal-verification/#the-ugly https://gavinhoward.com/2024/05/what-rust-got-wrong-on-forma... which says: > But there is an even harder problem: the C10M Problem. Is it possible to use RSC to handle 10 million connections, of which 1 million need some processing every second? (RSC being restricted structured concurrency.) IMO the C10M problem requires: a) user-land network stacks or unikernel servers, b) NPROC (or fewer) threads or processes, c) evented, continuation-passing style code in each of those threads or processes. I've written one such program (though without (a)), a HTTP read-only file server that does (b) and (c) and which supports "tailing" files by doing `GET`s with `Range: bytes=0-` (or some other starting offset, but no ending offset), and it scales to tens of thousands of concurrent clients trivially. To get to millions of clients I would need to use H/3 and QUIC, and also do (a). (That server also supports ETags and conditional requests. Tailing `GET`s end when the file is unlinked or renamed away. Essentially it is a poor person's Kafka.) This program stores state in a per-client data structure and in the form of a pointer to a continuation closure that is `{data structure, handler closure}` that is registered with the event system, and each handler does only non-blocking operations (if you can think of filesystem operations as non-blocking anyways, though one could also use aio). I bet this works well with RSC if all the state is kept in statically allocated objects. In my program all state is kept in dynamically allocated heap objects, but I could have statically allocated them instead, perhaps at program startup, or else at compile time. The point here is to absolutely minimize the representation of state. In a thread-per-client implementation the state is smeared on each thread's stack and also any necessary heap objects. In a CPS implementation the state is fully explicit, with none of it in any stack frames -- the programmer is in charge of producing the most compact state representation, and it's easy because the state has to be fully explicit. I view evented CPS and thread-per-client as the ends of a concurrency spectrum where green threads and co-routines are somewhere in the middle. If you want C10M you will probably end up wanting evented CPS. Green threads / fibers can get close to CPS if you work to minimize state anyways.
justincredible 2y ago
[dead]
silok 2y ago
People interested in this should also make sure to checkout Hylo, https://www.hylo-lang.org https://www.hylo-lang.org There are several presentations on the design and mechanisms. Eg - https://www.youtube.com/watch?v=ws-Z8xKbP4w https://www.youtube.com/watch?v=ws-Z8xKbP4w (Val: A Safe Language to Interoperate with C++ - Dimitri Racordon - CppCon 2022) - https://www.youtube.com/watch?v=oFupPFniD9s https://www.youtube.com/watch?v=oFupPFniD9s ([IWACO23] Borrow checking Hylo)

140 points by gavinhoward 2y ago

Wow, about Yao: "In fact, it might be better said that Yao is meant to be: As powerful as C, As flexible as Lisp, As easy as Python, As provable as Ada/SPARK, More reliable than Rust, With the time semantics of HAL/S." Even if I don't really believe in this incredible statement, I'm really curious to see what can be the result.

gavinhoward 2y ago
Author here. Yeah, you shouldn't believe it yet, but here is the status of each: * "As powerful as C": unproven. I might need something like Rust's `unsafe`, and even though I have something in mind for that, it requires that any program be expressible in Dynamic Restricted Structured Concurrency, an open problem. I am working on a proof, though. * "As flexible as Lisp": I think this is proven. Yao has equivalents for both macros (keywords) and reader macros (lexing modes). My build system uses its own keywords to implement a build DSL [1]. The shell sublanguage uses a lexing mode, and another makes it possible to embed JSON. * "As easy as Python": in retrospect, this isn't quite possible, but I hope to get 90% of the way. * "As provable as Ada/SPARK": I'll let you read the design in [2] and decide for yourself. But Yao will also have contracts. * "More reliable than Rust": unproven, but I think the lack of async will go a long way. * "With the time semantics of HAL/S": unproven. HAL/S was what the Shuttle software was written in [3]. It was hard real-time. Because Yao will be distributed in IR form [4], the back end could leverage knowledge of worst-case instruction latencies to calculate worst-case response times. This same thing will also allow using only constant-time instructions for cryptography, using a `constant_time` function trait. [1]: https://rigbuild.dev/build.rig5/#keywords https://rigbuild.dev/build.rig5/#keywords [2]: https://gavinhoward.com/2024/05/what-rust-got-wrong-on-formal-verification/ https://gavinhoward.com/2024/05/what-rust-got-wrong-on-forma... [3]: https://www.fastcompany.com/28121/they-write-right-stuff https://www.fastcompany.com/28121/they-write-right-stuff [4]: https://gavinhoward.com/2024/09/rewriting-rust-a-response/#distribution https://gavinhoward.com/2024/09/rewriting-rust-a-response/#d...
- az09mugen 2y ago
  Thank you very much for your detailed answer. Will look into your links right now.
- az09mugen 2y ago
  Hats off, you really did in fact a deep analysis of Rust conceptual errors by searching alternative ways to fix Rust async. Also by understanding and describing the decisions you made and what are their architectural implications (I liked the good, the bad and the ugly part). While I can't appreciate the entirety of this language because I can't grasp all the technical subtilities, I really like the core ideas at the basis of Yao and the spirit you put into it. I hope I can play with this language some day. And wish you good luck with this nice project.
  - gavinhoward 2y ago
    This is one of the nicest, yet honest, compliments I have ever received. Thank you!
- AlotOfReading 2y ago
  Worst case execution times are generally unknowable, even at codegen. It depends on things like the specific microarchitectural details, what other instructions are currently executing, the memory hierarchy, what instructions have been executed before, how the power supply is responding, what the thermal environment is like, etc. HAL/S dealt with these problems by a combination of programmer/validation discipline, custom hardware designed for hard real-time usecases, and generous support from the underlying RTOS (FCOS). Cryptography code doesn't deal with it, it just avoids data dependent nondeterminism, which is good enough for those use cases.
  - gavinhoward 2y ago
    Yes, you are correct. My idea is to cause a compile error if the backend can't use all instructions for which it knows the worst case latency or if it can't use purely constant-time instructions.

ubj 2y ago

Interesting response. I'm as curious as anyone else as to how Yao will improve upon Rust, but here is what I've observed from following several (relatively) recently created languages (Julia, Nim, Mojo, JAX): * Language creators start with high hopes and big promises. "We've learned from the past! This will solve all the problems of previous X,Y,Z languages! It will be so much easier to use!" * The language begins to be designed, implemented, and developed. Problems arise. Tradeoffs must be made. Invariably, the new language develops its own set of limitations, shortcomings, and weaknesses. These are inevitable with any new programming language. * Ultimately the language either finds a userbase who are willing to overlook or work around the limitations and pitfalls, or it fades away. * If it remains, eventually another new language arises saying "We've learned from the past! This will solve all the problems of previous X,Y,Z languages! It will be so much easier to use!" And the cycle repeats. Now, is this a bad thing? I would argue no, not necessarily. Every time a new language is created, our vision of what is possible is expanded. We learn new lessons about what works and what doesn't work in programming languages. So in short I'm looking forward to see how the state of the art is advanced by Yao. If it gets to a decent working state, I might even try it out if I have time. However, in light of the above statements forgive me for being skeptical of the following claim from Yao's website [1]: > As powerful as C, As flexible as Lisp, As easy as Python, As provable as Ada/SPARK, More reliable than Rust, With the time semantics of HAL/S. [1]: https://git.yzena.com/Yzena/Yc/src/branch/master/docs/yao/main.md https://git.yzena.com/Yzena/Yc/src/branch/master/docs/yao/ma...

gavinhoward 2y ago
Author here. You are absolutely right to be skeptical. I wrote that a long time ago. I did detail the current status of those claims in a comment: https://news.ycombinator.com/item?id=41672316 https://news.ycombinator.com/item?id=41672316 .
jadbox 2y ago
Fwiw, Zig is one of the few languages on my radar that's on the uptick. At least in my circle, I know people from firmware to VM development that moved from Rust over to Zig for its flexibility. There' also Bun that managed to nearly be a drop-in replacement for Node in a very short development cycle, which they claim is due to Zig. (I am not associated with Zig nor have a lot of experience with it yet)

steveklabnik 2y ago

I am always glad to see people pursuing creating their own programming language. More people should give it a try, IMHO. A tricky thing that comes up with Rust comparisons is that often, Rust has a feature that's weird or hard to use, but it's because that's the only solution that makes sense within the constraints Rust has placed upon itself. Clicking some links gets me to https://git.yzena.com/Yzena/Yc/src/branch/master/docs/yao/design.md https://git.yzena.com/Yzena/Yc/src/branch/master/docs/yao/de... > Yao's biggest goals are: Correctness, Convenience, Performance, in that order. Having clear goals is a great thing when making a language, because they give you guidance on what is appropriate to include and what is not. Rust has certainly demonstrated having similar goals, but in a slightly different order: Correctness, Performance, and then Convenience. So it wouldn't shock me if Yao could do some things better than Rust, in accordance with its goals. But that also means that sometimes, Rust would be useful where Yao cannot be. Everything is tradeoffs. Incidentally, I actually think that figuring out what your values are, and what your needs are, is a great way to pick a programming language. Decide what matters to you as an engineer, and then find a language that shares similar values. I gave a conference talk a few years back on this idea, and how I viewed Rust's values at the time https://www.infoq.com/presentations/rust-tradeoffs/ https://www.infoq.com/presentations/rust-tradeoffs/ This was based off of bcantrill's Platform as a Reflection of Values, which was very influential on me. https://www.youtube.com/watch?v=Xhx970_JKX4 https://www.youtube.com/watch?v=Xhx970_JKX4 If you've ever heard about Oxide's focus on values, this is some of the older background on that.

gavinhoward 2y ago
I wish I could upvote you twice. I decided on my values because of bcantrill's talk. Everyone should watch it. A more complete list of my values is at https://git.yzena.com/Yzena/Yc/src/branch/master/docs/adl/0000-values.md https://git.yzena.com/Yzena/Yc/src/branch/master/docs/adl/00... .
- andai 2y ago
  Could you elaborate on value #0 being users (and what it means to prioritize users over programmers)?

sgt 2y ago

Glad I waited before starting with Rust. Now I can just jump straight to Yao. Rust is so early 2020s.

bregma 2y ago
You're still using Yao? Pfff.
- chipdart 2y ago
  > You're still using Yao? Pfff. One-up flex master right here. Unbeatable.
  - sgt 2y ago
    Hip crowd's already moved on to Tcl, I know (with the advancements in v9.0 and all).
    - Ygg2 2y ago
      Tcl is yesterday's news. Hip crowd moved to artisanal ASM.
      - falcor84 2y ago
        Excuse me, but real programmers use butterflies https://xkcd.com/378/ https://xkcd.com/378/
- epage 2y ago
  > Pfff Now I want a language named that.
gavinhoward 2y ago
Please don't jump to Yao! The only thing it's good for right now is to replace shell scripts.

wizzwizz4 2y ago

> Instead of marking asynchronous functions, languages should have had us mark synchronous functions […] Although that wouldn’t remove the possibility of bugs when calling a blocking function in async code, So mark "synchronous" (i.e., non-yielding) and "asynchronous" (i.e., non-blocking). Then we can have the synchronous colour, the asynchronous colour, functions that are both (e.g. pure CPU-bound tasks, like arithmetic), and functions that are neither (e.g. buggy code).

Animats 2y ago

Mostly an ad for Yao. - Is there really a major use case for function traits? Is more elaboration of the type system actually useful? - The original "Rewriting Rust" article discussed replacing Rust's macro system. That's not mentioned here. If you had to write your macros in Rust, to be run in compile time, would that be a win? I doubt it. Each macro would start with a call to a parser, and then you generate code as strings. This would pay off only for complex cases such as a regular expression compiler. Rust already has compile-time build programs, where you can run Rust during the build process. (I use that to take in an API definition from another source and generate Rust.) - "Runtime capabilities" seems to be an attempt to build a container system into the language. It's not clear that helps much. That's really the OS's job. Protecting programs against themselves is nice, but not usually the problem. I'd like to see something in Android that gives an app file access with less access than "all files". Like "Can read what was installed for this app, can write working subdirectory for this app, and nothing else."

gavinhoward 2y ago
Fair criticisms, John. I just want to address macros. Yao has something like Rust's macros. They are called "keywords," because even the built-in keywords are implemented that way. (That is why Yao can just not have a `while` keyword.) My Yao-based build system, Rig, uses keywords to implement a build DSL. [1] And keywords are fast to compile. [1]: https://rigbuild.dev/build.rig5/#keywords https://rigbuild.dev/build.rig5/#keywords
nicoburns 2y ago
> Is there really a major use case for function traits? Absolutely. They can be used for function overloading, and for manually creating closures from structs, which can be more ergonomic sometimes. Whether you want those features is another matter. The rust compiler supports them but doesn't expose them to stable rust.
ruthmarx 2y ago
> 'd like to see something in Android that gives an app file access with less access than "all files". SELinux has been able to solve that problem in Android for a long, long time now. Which is more appropriate, as you say it should be the job of the OS. The problem is the age old one where users want convenience at the cost of security.

osigurdson 2y ago

Without sounding too much like a Cathy Woods, I'm wondering if AI can be leveraged to help with all of the non-core aspects of creating new languages? For example, really why does every language really need a json parser, or http requests library. If one were to examine the machine code instructions involved in each, they would likely be rather similar after all. Writing all of that stuff is an enormous lift for the community. Tooling is similarly "undifferentiated heavy lifting" in a way. Also, moving existing code bases to new languages is still hard. If there were better ways to achieve these things, there would be much less inertia in the language space.

tazjin 2y ago

Odd post, and it landed me on the Yzena website which is very surreal. It seems to be intentionally hard from the website to figure out what Yzena is or why anyone would want to buy a license for it (or the things it makes?). There was a link to a repo full of perl scripts, though. According to the website I'm not allowed to ask about this though ;)

gavinhoward 2y ago
I only have one Perl script in that repo... Anyway, Yzena is my business. I am not a very good marketer, and the website is bad. I also don't think I will get any business, but eh.

dang 2y ago

Recent and related: Rewriting Rust - https://news.ycombinator.com/item?id=41654871 https://news.ycombinator.com/item?id=41654871 - Sept 2024 (385 comments)

andai 2y ago

>Yao can’t be compiled in the traditional way. >Instead, Yao will be compiled to an LLVM-like IR (which already exists), and that’s how it will be distributed. Users will have to do the final compile step on their local machines. Is this referring to the compiler itself, or programs written in Yao?

gavinhoward 2y ago
Programs written in Yao.
- kibwen 2y ago
  If the goal is portability, Google pursued the idea of distributing cross-platform LLVM IR via PNaCl and ultimately abandoned it, because LLVM IR isn't really designed for portability.
  - gavinhoward 2y ago
    I designed my own, uncreatively called Yvm. Yao already compiles to it.

andai 2y ago

Is there something like this but without concurrency? I don't need concurrency or multithreading, and most of my pain with Rust has come from the fact that it prevents me from doing things that I know are correct because it thinks my code will run in a multithreaded environment (it will not). It seems like Yao's whole project is solving the concurrency problem. I'm like, why not drop it entirely (if performance isn't one of the language's top priorities anyway)? What does keeping it gain that's so important? (Context: I don't understand concurrency and multithreading.)

gavinhoward 2y ago
Good question. Yao's concurrency will be explicit. You will not get concurrency unless you open a threadset and spawn threads. Yao scripts run in a single thread by default. I focused on solving the concurrency problem because if it is solved, single thread code is solved as well.
skitter 2y ago
> it prevents me from doing things that I know are correct because it thinks my code will run in a multithreaded environment Could you elaborate on that? In your case you don't need to worry about Send/Sync, you can use Cell/RefCell, etc. The borrow checker isn't about threading, it's useful in a purely single-threaded context too.
- School-Cotton 2y ago
  Not OP but don’t a lot of async libraries require things to be Send because they assume they’ll run on a multithreaded executor?
ruthmarx 2y ago
> I don't need concurrency or multithreading, > ... > Context: I don't understand concurrency and multithreading. I get not needing it, but if you don't understand concurrency or multithreading how are you so certain you don't need concurrency or multithreading?
klabb3 2y ago

j1elo 2y ago

> that language is coming into existence right now! It is called Yao. Wasn't it called Mojo? It's been a while since I saw traction of that new language over here. Anyhow, it is interesting how many new languages are appearing every day. The bar is indeed constantly moving upwards.

mepian 2y ago
Mojo is completely unrelated, created by Chris Lattner and his team at Modular AI.
- deleted 2y ago
  [deleted]

cryptonector 2y ago

> This is actually the root of the function color problem: async is exactly backwards! Instead of marking asynchronous functions, languages should have had us mark synchronous functions, and then async should have been the default! What happens when you need to add a new trait that all existing functions must be changed to have? That's why async is generally an attribute. The answer is that we'd have to say that all functions have some default trait set that can be extended automatically as the language evolves, except those anti-traits they have. Then we could say that a function is async meaning "not sync", or even we could write !sync instead of async. I rather like the idea that you have to write `!sync` instead of `async`.

gavinhoward 2y ago
The post answers that. Every unmarked function can do anything. If you add a new thing that functions can do, you assume unmarked functions can do it (even if they don't), and you add a trait for the negative.
- cryptonector 2y ago
  Thanks, I got interrupted in my reading.

klabb3 2y ago

> The Rust async book mentions three more methods: […] Hah, I wrote this section and was deeply aware of these problems at the time. Let’s just say it didn’t fit in the introduction. In fact, a lot of the understanding of this issue has been expressed later, blog post by blog post, largely without coordination. It’s almost eerie to see again and again people encountering the same issue, and spending huge effort to address it (this one takes the prize though - making your own language). Let me try a to narrativize it: we have a fundamental problem with unrestricted concurrent control flow (very similar to how we used to have unrestricted sequential control flow when we had goto). This problem exists in most programming languages, but we mostly pretend it’s not there (and live with the subtle bugs instead). However, with Rust’s unique ownership- and safety model, the lack of structured concurrency was an unavoidable problem, at collision course with Rust itself. In the Rust we have today (without structured concurrency), a bunch of expected and reasonable behaviors cannot be achieved (such as borrowing from a parent task).

throwaway17_17 2y ago
Do you know of any longer form content that walks through this area, or maybe just a listing of blogs. I have a feeling the resources are relatively scattered over various sites and across time, so any tips on search terms to use if a deep dive into this problem (both in Rust and generically in programming language semantics) intrigues me?
- genter 2y ago
  https://vorpus.org/blog/notes-on-structured-concurrency-or-go-statement-considered-harmful/ https://vorpus.org/blog/notes-on-structured-concurrency-or-g... https://dubroy.com/blog/handling-user-input-with-structured-concurrency/ https://dubroy.com/blog/handling-user-input-with-structured-... The first one is particularly good. Both of those have links to more topics.
- klabb3 2y ago
  Sibling already gave great pointers to structured concurrency in general. For rust specifically the links in the post were good, some I hadn’t seen that came up in the last 2 years. Perhaps someone from deep PL background has more rigorous papers and such to point to? I highly doubt this is being discovered now for the first time – it wouldn’t surprise me if there’s a whole academic sub-branch about similar things. Given how important concurrency is, and how difficult it is to get right, there’s a lot of opportunity for academia to tackle the problem space. We sure as hell need it.

divs1210 2y ago

This discussion is seriously lacking in references to Koka language[0]. Koka is memory safe without using traditional GC, has effects, and is pretty cool over all. [0] https://koka-lang.github.io/koka/doc/index.html https://koka-lang.github.io/koka/doc/index.html

SkiFire13 2y ago
Reference counting is ultimately a GC, although not a tracing GC which is the most common kind. I also don't really see the appeal of not having a GC in a language like that. If it doesn't compete with C/C++ for performance and low level support then not having a GC is no longer an advantage. That said Koka still remains very cool for the effect system though, and I would really like to see it in a mainstream language!

tmtvl 2y ago

Serious mode: it's good that people are exploring the programming language space, both tiny and big changes can mean a world of difference in reducing bugs and making programs nicer both for the user to run and the developer to create and maintain. Serious mode off. When will we get Yao in the Linux kernel?

gavinhoward 2y ago
> Serious mode off. When will we get Yao in the Linux kernel? As soon as someone pays me long enough to get it there. :) I only have 3 hours max a day (usually only 2) to work on Yao. And I have other projects I want to do as well. But if someone paid, I sure could find the desire to work on it.
fuzztester 2y ago
>Serious mode off. When will we get Yao in the Linux kernel? Yaol can get involved and help with that, yaol know? Serious_mode_still_off? true

cryptonector 2y ago

Slightly off-topic, but TFA links to https://gavinhoward.com/2024/05/what-rust-got-wrong-on-formal-verification/#the-ugly https://gavinhoward.com/2024/05/what-rust-got-wrong-on-forma... which says: > But there is an even harder problem: the C10M Problem. Is it possible to use RSC to handle 10 million connections, of which 1 million need some processing every second? (RSC being restricted structured concurrency.) IMO the C10M problem requires: a) user-land network stacks or unikernel servers, b) NPROC (or fewer) threads or processes, c) evented, continuation-passing style code in each of those threads or processes. I've written one such program (though without (a)), a HTTP read-only file server that does (b) and (c) and which supports "tailing" files by doing `GET`s with `Range: bytes=0-` (or some other starting offset, but no ending offset), and it scales to tens of thousands of concurrent clients trivially. To get to millions of clients I would need to use H/3 and QUIC, and also do (a). (That server also supports ETags and conditional requests. Tailing `GET`s end when the file is unlinked or renamed away. Essentially it is a poor person's Kafka.) This program stores state in a per-client data structure and in the form of a pointer to a continuation closure that is `{data structure, handler closure}` that is registered with the event system, and each handler does only non-blocking operations (if you can think of filesystem operations as non-blocking anyways, though one could also use aio). I bet this works well with RSC if all the state is kept in statically allocated objects. In my program all state is kept in dynamically allocated heap objects, but I could have statically allocated them instead, perhaps at program startup, or else at compile time. The point here is to absolutely minimize the representation of state. In a thread-per-client implementation the state is smeared on each thread's stack and also any necessary heap objects. In a CPS implementation the state is fully explicit, with none of it in any stack frames -- the programmer is in charge of producing the most compact state representation, and it's easy because the state has to be fully explicit. I view evented CPS and thread-per-client as the ends of a concurrency spectrum where green threads and co-routines are somewhere in the middle. If you want C10M you will probably end up wanting evented CPS. Green threads / fibers can get close to CPS if you work to minimize state anyways.

justincredible 2y ago

[dead]

silok 2y ago

People interested in this should also make sure to checkout Hylo, https://www.hylo-lang.org https://www.hylo-lang.org There are several presentations on the design and mechanisms. Eg - https://www.youtube.com/watch?v=ws-Z8xKbP4w https://www.youtube.com/watch?v=ws-Z8xKbP4w (Val: A Safe Language to Interoperate with C++ - Dimitri Racordon - CppCon 2022) - https://www.youtube.com/watch?v=oFupPFniD9s https://www.youtube.com/watch?v=oFupPFniD9s ([IWACO23] Borrow checking Hylo)