• @wim
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    1410 months ago

    Maybe it’s just me, but isn’t async programming a mess in all programming languages?

      • @vrighter@discuss.tchncs.de
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        10 months ago

        not really. first of all async in not the same as threading. And even then, while it makes parallel code easier to write (not easier to reason about), it still has the exact same footguns as anything else, as soon as you venture away from having only one consumer for every producer. Synchronization is still all on you

      • @wim
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        610 months ago

        That’s a whole different thing to me. That’s not async, that’s channels and multithreading.

        I do that in Rust as well with mcsp channels and it’s been fine.

        It’s the async/await bit that I find incredibly akward all the time.

        • Channels and multithreading are a solution to async problems. Instead of a keyword trying to abstract away the async, you use a mechanism for communicating between coroutines. You can run Go with a single execution thread and still get benefits from goroutines and channels. In fact, Go didn’t turn on multithreading until 1.5.

          Go solves async with goroutines and channels, not with an async keyword. The runtime is pretty heavy and steps in when standard library functions would block. In other words, it’s async by default since blocking IO causes another goroutines to execute.

          • Júlio Gardona
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            110 months ago

            @sugar_in_your_tea @wim
            go channels and goroutines are very good and easy to work, but thei cant acquire the performance and security of #tokio. You can write good code and solutions with goroutines, but there are limitations. #Rust async is a bit more difficult to do, but its not so or too complicated or dificult, and you will choose between the two languages by kind of problems you want to solve.

            • Yes, there’s absolutely a lot of good reasons to use Rust over Go, even for heavily async tasks, I’m merely saying that Go supporting channels in the language makes it a lot easier to use for async tasks. There’s one proper way to send data between concurrent contexts, and that’s a channel, so it gets used a ton in library code.

              Rust could get a lot of that benefit by including channels in the standard library. We could still keep the async reactor code out of the standard library, but we’d need trait definitions there so the channels could hook into them.

              I personally think the Rust standard library should ship a complete async solution, with core bits being overridable (like with memory allocation), which would make it a lot easier to write clean async logic. I think the standard library should be single threaded, but be multi-threaded compatible, and then allow third party libraries to provide the multi-threaded capability.

          • They’re very similar, but with very different ergonomics. Go channels are part of the language, so libraries use them frequently, whereas tokio is a separate library and not nearly as ubiquitous. So you’ll get stuff like this:

            c := make(chan bool)
            go func () {
                time.Sleep(time.Second*2)
                c <- true
            } ()
            
            select {
            case val := <-c:
            case _ := <-time.After(time.Second)
            }
            

            This lets you implement a simple timeout for a channel read. So the barrier to using them is really low, so they get used a ton.

            I haven’t looked at the implementation of tokio channels, so I don’t know if there’s something subtly different, but they do have the same high level functionality.