Async/Await is finally back in Zig

Node is one place where async-await has zero counter arguments and every alternative is strictly worse.

https://nodejs.org/en/about

Node is not a web page, so no reason to limit it to the same patterns.

Then, the next issue would be thread safety. But that could be treated as a separate problem.

The motivation for node was that users wanted to use JavaScript on the server.

Node dictates that when faced with an async function the result is that I must either implement async myself so I can do await or go into callback rabbit holes by doing .then(). If the function author is nice, they will give me both async and sync versions: readFile() and readFileSync(). But that sucks.

The alternative would be that 1) the decision to go async were mine; 2) the language supports my decision with syntax/semantics.

Ie. if I call the one and only fs.readFile() and want to block I would then do

       sync fs.readFile()

1. https://www.npmjs.com/package/deasync

No, just callbacks and event handlers (and an interface like select/poll/epoll/kqueue for the OS primitives on which you need to wait). People were writing threadless non-blocking code back in the 80's, and while no one loved the paradigm it was IMHO less bad than the mess we've created trying to avoid it.

One of the problems I'm trying to point out is that we're so far down the rabbit hole in this madness that we've forgotten the problems we're actually trying to solve. And in particular we've forgotten that they weren't that hard to begin with.

What do you mean? A JS runtime can't do anything useful on its own, it can't read files, it can't load dependencies because it doesn't know anything about "node_modules", it can't open sockets or talk to the world in any other way - that's what Node.js provides.

> I would claim it was the only low-effort model available to them and therefore not motivation.

It was a headline feature when it released.

https://web.archive.org/web/20100901081015/https://nodejs.or...

In the above link Node could be described as a Chrome V8 distribution with modules enabling building a web server.

Adding threading to a non-threaded scripting runtime is another ball game.

The point is that Node was forced into this model by V8 limitations, then sold it as an advantage, however, it is only one way to solve the problem with its own trade-offs and you have to look at the specific use case you are looking at to see if it is really the best solution for your use case.

Yes, obviously, that's what NodeJS does. But you can't "just use the V8 runtime as-is if you're doing async IO", it doesn't have those facilities at all.

Async IO wasn't just "sold as an advantage", it is an advantage. Websockets were gaining popularity around that time and async IO is a natural fit for that.

You would have to change the language and boil the ocean to make the runtime support multiple threads (properly).

But why? Just to end up with the inferior thread-per-request runtime (which by the way, still needs to support async because it's part of the language), that requires developers to write JS which is incompatible with browser JS, which would've eliminated most of the synergy between the two?

I really don't understand what you're going for here. I don't see a single advantage here.

If you don't have many threads, OS threads are okay as well. It is all about memory and scheduling overhead.

But that is just my opinion. You are welcome to have a different opinion.