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- import { useEffect, useRef } from 'react';
- /**
- * Runs an effect only when the dependencies have changed, skipping the
- * initial "on mount" run. Caution, if the dependency list never changes,
- * the effect is **never run**
- *
- * ```ts
- * const ref = useRef<HTMLInput>(null);
- *
- * // focuses an element only if the focus changes, and not on mount
- * useUpdateEffect(() => {
- * const element = ref.current?.children[focusedIdx] as HTMLElement
- *
- * element?.focus()
- *
- * }, [focusedIndex])
- * ```
- * @param effect An effect to run on mount
- *
- * @category effects
- */
-
- function useUpdateEffect(fn, deps) {
- var isFirst = useRef(true);
- useEffect(function () {
- if (isFirst.current) {
- isFirst.current = false;
- return;
- }
-
- return fn();
- }, deps);
- }
-
- export default useUpdateEffect;
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