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zestyrx on March 23, 2023 | parent | context | favorite | on: You might not need an effect

Isn't this exactly what useLayoutEffect is for? https://react.dev/reference/react/useLayoutEffect

karaokeyoga on March 23, 2023 [–]

useLayoutEffect is called after the render cycle but before the “paint”. useMemo is called during the render cycle (i.e. immediately).

You can confirm this via console.log:

useMemo(() => console.log(1), [])

console.log(2)

… will print 1 then 2.

If you replace useMemo with useLayoutEffect, you’ll get 2 then 1.

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