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Joined 1 year ago
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Cake day: July 6th, 2023

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  • but futures only execute when polled.

    The most interesting part here is the polling only has to take place on the scope itself. That was actually what I wanted to check, but got distracted because all spawns are awaited in the scope in moro’s README example.

    async fn slp() {
        tokio::time::sleep(std::time::Duration::from_millis(1)).await
    }
    
    async fn _main() {
        let result_fut = moro::async_scope!(|scope| {
            dbg!("d1");
            scope.spawn(async { 
                dbg!("f1a");
                slp().await;
                slp().await;
                slp().await;
                dbg!("f1b");
            });
            dbg!("d2"); // 11
            scope.spawn(async {
                dbg!("f2a");
                slp().await;
                slp().await;
                dbg!("f2b");
            });
            dbg!("d3"); // 14
            scope.spawn(async {
                dbg!("f3a");
                slp().await;
                dbg!("f3b");
            });
            dbg!("d4");
            async { dbg!("b1"); } // never executes
        });
        slp().await;
        dbg!("o1");
        let _ = result_fut.await;
    }
    
    fn main() {
        let rt = tokio::runtime::Builder::new_multi_thread()
            .enable_all()
            .build()
            .unwrap();
        rt.block_on(_main())
    }
    
    [src/main.rs:32:5] "o1" = "o1"
    [src/main.rs:7:9] "d1" = "d1"
    [src/main.rs:15:9] "d2" = "d2"
    [src/main.rs:22:9] "d3" = "d3"
    [src/main.rs:28:9] "d4" = "d4"
    [src/main.rs:9:13] "f1a" = "f1a"
    [src/main.rs:17:13] "f2a" = "f2a"
    [src/main.rs:24:13] "f3a" = "f3a"
    [src/main.rs:26:13] "f3b" = "f3b"
    [src/main.rs:20:13] "f2b" = "f2b"
    [src/main.rs:13:13] "f1b" = "f1b"
    

    The non-awaited jobs are run concurrently as the moro docs say. But what if we immediately await f2?

    [src/main.rs:32:5] "o1" = "o1"
    [src/main.rs:7:9] "d1" = "d1"
    [src/main.rs:15:9] "d2" = "d2"
    [src/main.rs:9:13] "f1a" = "f1a"
    [src/main.rs:17:13] "f2a" = "f2a"
    [src/main.rs:20:13] "f2b" = "f2b"
    [src/main.rs:22:9] "d3" = "d3"
    [src/main.rs:28:9] "d4" = "d4"
    [src/main.rs:24:13] "f3a" = "f3a"
    [src/main.rs:13:13] "f1b" = "f1b"
    [src/main.rs:26:13] "f3b" = "f3b"
    

    f1 and f2 are run concurrently, f3 is run after f2 finishes, but doesn’t have to wait for f1 to finish, which is maybe obvious, but… (see below).

    So two things here:

    1. Re-using the spawn terminology here irks me for some reason. I don’t know what would be better though. Would defer_to_scope() be confusing if the job is awaited in the scope?
    2. Even if assumed obvious, a note about execution order when there is a mix of awaited and non-awaited jobs is worth adding to the documentation IMHO.

  • I skimmed the latter parts of this post since I felt like I read it all before, but I think moro is new to me. I was intrigued to find out how scoped span exactly behaves.

    async fn slp() {
        tokio::time::sleep(std::time::Duration::from_millis(1)).await
    }
    
    async fn _main() {
        let value = 22;
        let result_fut = moro::async_scope!(|scope| {
            dbg!(); // line 8
            let future1 = scope.spawn(async {
                slp().await;
                dbg!(); // line 11
                let future2 = scope.spawn(async {
                    slp().await;
                    dbg!(); // line 14
                    value // access stack values that outlive scope
                });
                slp().await;
                dbg!(); // line 18
    
                let v = future2.await * 2;
                v
            });
    
            slp().await;
            dbg!(); // line 25
            let v = future1.await * 2;
            slp().await;
            dbg!(); // line 28
            v
        });
        slp().await;
        dbg!(); // line 32
        let result = result_fut.await;
        eprintln!("{result}"); // prints 88
    }
    
    fn main() {
        // same output with `new_current_thread()` of course
        let rt = tokio::runtime::Builder::new_multi_thread()
            .enable_all()
            .build()
            .unwrap();
        rt.block_on(_main())
    }
    

    This prints:

    [src/main.rs:32:5]
    [src/main.rs:8:9]
    [src/main.rs:25:9]
    [src/main.rs:11:13]
    [src/main.rs:18:13]
    [src/main.rs:14:17]
    [src/main.rs:28:9]
    88
    

    So scoped spawn doesn’t really spawn tasks as one might mistakenly think!


  • Because non-open ones are not available, even for a price. Unless you buy something bigger than the “standard” itself of course, like a company that is responsible for it or having access to it.

    There is also the process of standardization itself, with committees, working groups, public proposals, …etc involved.

    Anyway, we can’t backtrack on calling ISO standards and their likes “open” on the global level, hence my suggestion to use more precise language (“publicly available and sharable”) when talking about truly open standards.








  • First of all, unsafe famously doesn’t disable the borrow checker, which is something any Rustacean would know, so your intro is a bit weird in that regard.

    And if you neither like the borrow checker, nor like unsafe rust as is, then why are you forcing yourself to use Rust at all. If you’re bored with C++, there are other of languages out there, a couple of which are even primarily developed by game developers, for game developers.

    The fact that you found a pattern that can be alternatively titled “A Generic Method For Introducing Heisenbugs In Rust”, and you are somehow excited about it, indicates that you probably should stop this endeavor.

    Generally speaking, I think the Rust community would benefit from making an announcement a long the lines of “If you’re a game developer, then we strongly advise you to become a Rustacean outside the field of game development first, before considering doing game development in Rust”.




  • Federation is irrelevant. Matrix is federated, yet most communities and users would lose communication if matrix.org got offline.

    With, transport-only distributablity, which i think is what radicale offers, availability would depend on the peers. That means probably less availability than a big service host.

    Distributed transport and storage would fix this. a la something like Tahoe-LAFS or (old) Freenet/Hyphanet. And no, IPFS is not an option because it’s generally a meme, and is pull-based, and have availability/longevity problems with metadata alone. iroh claims to be less of a meme, but I don’t know if they fixed any of the big design (or rather lack of design) problems.

    At the end of the day, people can live with GitHub/GitLab/… going down for a few minutes every other week, or 1-2 hours every other month, as the benefits outweigh the occasional inconvenience by a big margin.

    And git itself is distributed anyway. So it’s not like anyone was cut from committing work locally or pushing commits to a mirror.

    I guess waiting on CI runs would be the most relevant inconvenience. But that’s not a distributable part of any service/implementation that exists, or can exist without being quickly gravely abused.




  • Your answer wanders a bit unnecessarily IMHO.

    • no-std Rust has no run-time dependencies of its own.
    • std Rust runtime-requirements are basically libc, a heap allocator, and a threading library. Many implementations on many OSes are already supported, including musl on Linux. And what’s not supported can theoretically be so in the future.
    • Code generation at build-time is dependent on LLVM, with cranelift and (soon) GCC available as not fully mature alternatives.
    • 3rd party code/crates may impose additional requirements.


  • Ask yourself:

    • Where do these stats come from?
    • What do they actually measure?
    • How can the total number of all Desktop Linux users or devices be known to anyone?


    The fact of the matter is, none of these stats actually measure the number of users. Most of them are just totally flawed guestimates based on what is often limited web analytics data collected by them.

    In fact, not even the developers of a single distribution can guess the number of people/devices using/running that specific distribution. A distribution like Debian for example has mirrors, and mirrors to some mirrors, and maybe even mirrors to some mirrors to some mirrors. So if Debian developers can’t possibly know the number of Debian users, do you think OP’s site knows the total number of Desktop Linux users?

    And let’s not get into the fact that the limited data they collect itself is not even reliable. View desktop site on your Android phone’s browser. Congratulations! Now you’re a desktop Linux user. No special user-agent spoofing add-on needed. You’re even running X11. Good choice not following the Wayland fad too soon.