react-native-flip-book/lib/module/hooks/usePrevious.js

Page Flipper

"use strict";

import { useEffect, useRef } from 'react';

// Hook
const usePrevious = value => {
  // The ref object is a generic container whose current property is mutable ...
  // ... and can hold any value, similar to an instance property on a class
  const ref = useRef(undefined); // Initialize with undefined

  // Store current value in ref
  useEffect(() => {
    ref.current = value;
  }, [value]); // Only re-run if value changes

  // Return previous value (happens before update in useEffect above)
  return ref.current;
};
export default usePrevious;
//# sourceMappingURL=usePrevious.js.map