useTimer Custom Hook

useTimer.ts

import { useState, useEffect } from "react";

export const useTimer = (delay: number) => {
    const [clock, setClock] = useState(false);

    useEffect(
        () => {
            // toggle clock
            const handler = setInterval(() => {
                setClock((v) => !v);
            }, delay);

            return () => {
                clearInterval(handler);
            };
        },
        [delay]
    );
    return clock;
};


/* Usage:
import { useTimer } from './useTimer';

...
const timer = useTimer(delay);
useEffect(() => {...}, [timer]);
...
*/