import { useEffect, useRef } from 'react' export default function useInterval(callback: () => void, delay: null | number, leading = true) { const savedCallback = useRef<() => void>() // Remember the latest callback. useEffect(() => { savedCallback.current = callback }, [callback]) // Set up the interval. useEffect(() => { function tick() { const current = savedCallback.current current && current() } if (delay !== null) { if (leading) tick() const id = setInterval(tick, delay) return () => clearInterval(id) } return undefined }, [delay, leading]) }