title: How to get changes in Vue updated hook?
body: <p>If I have a Vue component like:</p>
  
  <pre><code>&lt;script&gt;
    export default {
      updated() {
        // do something here...
      }
    };
  &lt;/script&gt;
  </code></pre>
  
  <p>is there anyway to get the changes that resulted in the update? Like how <code>watch</code> hooks accept arguments for previous and next data?</p>
  
  <pre><code>watch: {
    someProp(next, prev) {
      // you can compare states here
    }
  }
  </code></pre>
  
  <p>React seems to do this in <code>componentDidUpdate</code> hooks, so I'm assuming Vue has something similar but I could be wrong.</p>