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- import { useEffect, useRef } from 'react';
- /**
- * Store the last of some value. Tracked via a `Ref` only updating it
- * after the component renders.
- *
- * Helpful if you need to compare a prop value to it's previous value during render.
- *
- * ```ts
- * function Component(props) {
- * const lastProps = usePrevious(props)
- *
- * if (lastProps.foo !== props.foo)
- * resetValueFromProps(props.foo)
- * }
- * ```
- *
- * @param value the value to track
- */
-
- export default function usePrevious(value) {
- var ref = useRef(null);
- useEffect(function () {
- ref.current = value;
- });
- return ref.current;
- }
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