Files F100871964

useUpdateImmediateEffect.js
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Created: Mon, Feb 3, 11:53

useUpdateImmediateEffect.js
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	import { useRef } from 'react';
	import useStableMemo from './useStableMemo';
	import useWillUnmount from './useWillUnmount';
	/**
	* An _immediate_ effect that runs an effect callback when its dependency array
	* changes. This is helpful for updates should must run during render, most
	* commonly state derived from props; a more ergonomic version of https://reactjs.org/docs/hooks-faq.html#how-do-i-implement-getderivedstatefromprops
	*
	* ```ts
	* function Example({ value }) {
	* const [intermediaryValue, setValue] = useState(value);
	*
	* useUpdateImmediateEffect(() => {
	* setValue(value)
	* }, [value])
	* ```
	*
	* @category effects
	*/

	function useUpdateImmediateEffect(effect, deps) {
	var firstRef = useRef(true);
	var tearDown = useRef();
	useWillUnmount(function () {
	if (tearDown.current) tearDown.current();
	});
	useStableMemo(function () {
	if (firstRef.current) {
	firstRef.current = false;
	return;
	}

	if (tearDown.current) tearDown.current();
	tearDown.current = effect();
	}, deps);
	}

	export default useUpdateImmediateEffect;

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