How to use the usePrevious hook for tracking the previous state of a variable in Next.js

In Next.js, you can use the usePrevious hook to track the previous state of a variable. However, it's important to note that usePrevious is not a built-in hook in React. You will need to create it yourself. Here's an example of how you can implement the usePrevious hook in a Next.js project:

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import { useEffect, useRef } from 'react';

function usePrevious(value) {
  const ref = useRef();

  useEffect(() => {
    ref.current = value;
  }, [value]);

  return ref.current;
}

// Example usage in a component
function MyComponent() {
  const [count, setCount] = useState(0);

  // Get the previous value of 'count'
  const prevCount = usePrevious(count);

  return (
    <div>
      <p>Current Count: {count}</p>
      <p>Previous Count: {prevCount}</p>
      <button onClick={() => setCount(count + 1)}>Increment</button>
    </div>
  );
}

In the usePrevious hook, a useRef is used to store the previous value of the variable. The useEffect hook is used to update the ref whenever the value changes. The previous value is then accessed through the ref.current property.

Make sure to import useEffect and useRef from the 'react' package.

This example demonstrates tracking the previous state of the count variable in a component. You can adapt it for other variables as needed.