22 lines
589 B
JavaScript
22 lines
589 B
JavaScript
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import { useCallback, useEffect, useState } from 'react';
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/**
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* Polyfill for React 19's useOptimistic.
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* Shows optimistic state immediately; reconciles when passthrough changes.
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*/
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export function useOptimistic(passthrough, reducer) {
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const [optimistic, setOptimistic] = useState(passthrough);
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// Whenever the server-confirmed state lands, sync it in.
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useEffect(() => {
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setOptimistic(passthrough);
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}, [passthrough]);
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const dispatch = useCallback(
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action => setOptimistic(current => reducer(current, action)),
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[reducer],
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);
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return [optimistic, dispatch];
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}
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