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Comment by weatherlight | Hacker News Reader

    export const Child2Animation = 
      Co.Repeat(
        Co.Seq([
          Co.SetState(Child2.Updaters.Core.a(replaceWith(1)).then(
            Child2.Updaters.Core.b(replaceWith("")))),
          Co.Wait(250),
          Co.For(Range(0, 3))(
            _ =>
              Co.Seq([
                Co.SetState(Child2.Updaters.Core.a(_ => _ * 2)),
                Co.Wait(250),
                Co.SetState(Child2.Updaters.Core.b(_ => _ + ".")),
                Co.Wait(250),
              ])
          )
        ])
      );

> Not only is the code pretty self explanatory.

Is it though?

View on HN

> but the alternative implementation of state machines in any frontend framework would look terrible

  async function animation(setState, signal) {
    while (true) {
      setState("a", 1)
      setState("b", "")
      await wait(250)
      signal.throwIfAborted()

      for (_ of range(0, 3)) {
        setState("a", (_) => _ * 2)
        await wait(250)
        signal.throwIfAborted()
        setState("b", (_) => _ + ".")
        await wait(250)
        signal.throwIfAborted()
      }
    }
  }

I love FP. but this is way more readable than the above. It doesn't fight the ergonomics of javascript.

I think a "before" comparison would've really helped with this example. I'd also argue a state machine approach has the added benefit of allowing you to enter the sequence at any point. If you use `Co.Seq` to e.g. build a form flow, it'd be hard to test or serialize into the middle of the sequence.

There may be something interesting here but it's pretty hard to bite into.

Yea, it is. Granted you have to understand the words used in the explanation.

If your bar for “self-explanatory” is “teaches you both the words and the concepts” then there aren’t any self-explanatory frameworks at all?

> Ballerina integrates the state of the art in functional programming and even category theory.

It's.. just typescript?

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