Svelte 5: Runes not tracking async dependencies about svelte HOT 5 OPEN

@valterkraemer That would break far too many cases as we now use runtime reactivity rather than compile time reactivity.

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This is to be expected. Runes are designed to read dependencies sync only – and given the browser has no native way to track async context (yet), this isn't possible to do otherwise.

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This is to be expected. Runes are designed to read dependencies sync only – and given the browser has no native way to track async context (yet), this isn't possible to do otherwise.

Thanks, that's what I assumed, but couldn't find any documentation/issue related to it.

I guess the compiler could traverse the inside of e.g. $derived and find all the dependencies though 🤔

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@valterkraemer What if you call a function from a random npm module? The compiler is limited in context.

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@valterkraemer What if you call a function from a random npm module? The compiler is limited in context.

I was thinking just the variables used inside of the $derived block, not calls to code outside of it. But yeah, that's probably not a good idea.

Then this would work

let derivedId = $derived.by(() => {
  return Promise.resolve().then(() => chatId);
});

But not this

function myFunc() {
  return Promise.resolve().then(() => chatId);
}

let derivedId = $derived.by(myFunc);

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