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ReactAdvanced#performance
ReactAdvanced#hooks#performance
Difference between useMemo and useCallback?
useMemo caches a computed value between renders; useCallback caches a function identity. Both take a dependency array and exist to avoid expensive recomputation or unnecessary re-renders of memoized children.
Example
const sorted = useMemo(() => items.sort(cmp), [items]); const onPick = useCallback(id => setPick(id), []);