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I‘m really unsure if I like the linkedSignal idea. It feels so much like useEffect to synchronize two states which is kind of a code smell (cc @tkdodo.eu) but they make an interesting case…

yeah I actually like the `computed` solution they are showing in the post. In React, I'd do: function ItemList({ items }) { const [item, setItem] = useState() // prefer user selection, fallback to first item const selectedItem = item ?? items[0] } deriving state better than syncing it

In their example, the selected item should reset to the first item whenever the items change. If the old item is no longer part of items, you could still do this with derivation, but if you want to always reset, when items change, then it would be tricky to get around an effect…

Okay then I misunderstood the example, but isn't that .. bad? Like, let's I have a dropdown with 5 elements. I select the second one. Now a new element is added (background refetch), the list now has 6 elements. Why would that undo my selection?

We can say: fall back to the first item if the item chosen by the user is no longer valid, and that's fair, but we can still do that with derived state: