Comment by andrewstuart
4 days ago
I like async and await.
I understand that some devs don’t want to learn async programming. It’s unintuitive and hard to learn.
On the other hand I feel like saying “go bloody learn async, it’s awesome and massively rewarding”.
Intuition is relative: when I first encountered unix-style synchronous, threaded IO, I found it awkward and difficult to reason about. I had grown up on the callback-driven classic Mac OS, where you never waited on the results of an IO call because that would freeze the UI; the asynchronous model felt like the normal and straightforward one.
> It’s unintuitive and hard to learn.
Funny, because it was supposed to be more intuitive than handling concurrency manually.
It is a tool. Some tools make you more productive after you have learned how to use them.
I find it interesting how in software, I repeatedly hear people saying "I should not have to learn, it should all be intuitive". In every other field, it is a given that experts are experts because they learned first.
> I find it interesting how in software, I repeatedly hear people saying "I should not have to learn, it should all be intuitive". In every other field, it is a given that experts are experts because they learned first.
Other fields don't have the same ability to produce unlimited incidental complexity, and therefore not the same need to rein it in. But I don't think there's any field which (as a whole) doesn't value simplicity.
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Except you're hearing it from someone who doesn't have a problem handling state machines and epoll and manual thread management.
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It is. A lot.
But concurrency is hard and there's so much you syntax can do about it.
Some come to async from callbacks and others from (green)threads.
If you come from callbacks it is (almost) purely an upgrade, from threads is it more mixed.
Yeah, that's what annoys me, async comes from people who only knew about callbacks and not other forms of inter thread communication.
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Frankly, async being non-intuitive does not imply that manual concurrency handling is less so; both are a PITA to do correctly.
It IS intuitive.
After you’ve learned the paradigm and bedded it down with practice.
It is an intrinsic tradeoff. With async there is significantly more code complexity with substantially higher performance and scalability.
If you don't need the performance and scalability then it is not unreasonable to argue that async isn't worth the engineering effort.
I can't follow that it's hard to learn and unintuitive
What's awesome or rewarding about it?
It forces programmers to learn completely different ways of doing things, makes the code harder to understand and reason about, purely in order to get better performance.
Which is exactly the wrong thing for language designers to do. Their goal should be to find better ways to get those performance gains.
And the designers of Go and Java did just that.
> It forces programmers to learn completely different ways of doing things, makes the code harder to understand and reason about, purely in order to get better performance.
Technically, promises/futures already did that in all of the mentioned languages. Async/await helped make it more user friendly, but the complexity was already there long before async/await arrived
Yes - I was really talking about "asynchronous programming" in general, not the async/await ways to do it in particular.
What different way of doing things?
If I want sequential execution, I just call functions like in the synchronous case and append .await. If I want parallel and/or concurrent execution, I spawn futures instead of threads and .await them. If I want to use locks across await points, I use async locks, anything else?
Or... we've learned it and don't like it? For legitimate reasons?
Really? async/await is the model that makes it really easy to ignore all the subtleties of asynchronous code and just go with it. You just need to trial and error where/when to put async/await keywords. It's not hard to learn. Just effort. If something goes wrong, then "that's just how things go these days".