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Discussion on: Don't over useState

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Replies for: I don’t see why - quite the opposite actually. Before: initial render - fetch effect does setState, triggers render - effect that syncs data runs, ...

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Dominik D •

What we do is calling computeCategories in every render, which we didn’t do before. This doesn’t matter unless this function is expensive. If we have proof that we need to optimize it, we can do:

const categories = React.useMemo(
  () => data ? computeCategories(data) : [],
  [data]
)
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and now we call that function the same amount of times as before.