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    Handle Deep Object Comparison in React's useEffect hook with the useRef Hook

    reactReact
    ^16.7.0-alpha

    The second argument to React's useEffect hook is an array of dependencies for your useEffect callback. When any value in that array changes, the effect callback is re-run. But the variables object we're passing to that array is created during render, so our effect will be re-run every render even if the shape of the object is the same. So let's solve this by doing our own equality check from within the effect callback.