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Comment by threatofrain | Hacker News Reader

What's the status of cancellable promises in proposal land?

I mean, why would you want to "cancel" a Promise? You can already cancel HTTP requests, what are some other things you want to cancel really?

If you don't want to continue with something inside a Promise, just pass in something that could be changed from `true` to `false` and it cancels itself based on that.

I've had this same cancellation conversation many times with JS programmers. I think it's fair to say there's a need for standardization. Evidence for this need is network request management is really poor in pretty much all JS apps.

Specifically the case of request management, it's already implemented and available in all browsers practically. It's like four lines of code you have to add/change, to be able to cancel a request. https://developer.mozilla.org/en-US/docs/Web/API/AbortContro...

Regarding other cases, there are already ways of handling those. I don't think just because many ask about something, doesn't mean it's not currently working.

There are a lot of issues with the ergonomics of AbortController. It's very low level.

Did you actually look at the link I sent you? It's absolutely not low level. If you know how to use window.fetch, you know how to use AbortController already.

   controller = new AbortController();
   const signal = controller.signal;
   fetch("http://example.com", { signal: signal })
   // abort request
   controller.abort();

It basically couldn't be simpler? What sort of API would you like to be able to cancel requests?

That's a toy example! In reality in a complex app you'd usually be aborting far from where the fetch is created, and you'd have large promise chains where the semantics of cancellation are non-obvious and even unintuitive.

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