Comment by knuthsat | Hacker News Reader

Comment by knuthsat | Hacker News Reader

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Sometimes you don't want to pause (with await) and give something else the chance to execute (happens a lot in UI).

When code is sloppily written you realize that at some point you can't use much of the existing code outside of async.

One nice example of polluting the codebase is having async local storage. Now everything that reads from the storage needs to be annotated async and now your initialization pipeline might be insanely async. Good way to avoid it is to read the whole local storage at the beginning (having a sync interface) and then everyone just reads without await.

From recent experience, I did exactly that with storage and ended up removing thousands of async annotations that were no longer necessary.

Similar "mistakes" happen for other things and then at some point you are putting loading guards everywhere because your async operations are always awaiting and letting the UI update when it should not.

Behind async there is a real actual hardware reality. Accessing local storage (or the network) is slow and you do not want to block your UI.

You say async were all over the place. Either it makes sense because fundamentally, what you are doing IS asynchronous. Or it make no sense because the asynchronous nature of you calls are not important in your design (I don't see why but ok), in that case you can always break the chains by using a promise:

    async bar() {
      return await baz();
    }

    foo() {
      const promise = bar();
      promise.then(() => {}); // don't care...
    }

Yes, but the usual cases of -> "app starts -> load some state from local storage -> store it in memory for sync access -> do app" sometimes get lost due to the ease of async/await syntax.

If you have to chain network requests but each request depends on results of the former ones, then async/await makes it really pretty.

I have no idea how much async/await is too much.

What I do dislike is that storage loads, network requests and other things are tied to the same type, so when you look at code, you have no idea what's happening inside those async functions, but that story is for some other time.

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