title: Return true if a object is set to undefined in an array of objects
body: <p>I would like to know how can I check if any object in an array of object is set to undefined.</p>
  
  <p>How can I check if the 'author' is set to undefined?</p>
  
  <pre><code>const state = {
    sortBook: [
      { title: 'asc' },
      { author: undefined }
    ]
  };
  </code></pre>
  
  <p>The main thing is that this array changes dynamically. So as the user set the data it could be: </p>
  
  <pre><code>const state = {
    sortBook: [
      { title: 'asc' },
      { editionYear: undefined }
    ]
  }
  </code></pre>
  
  <p>So I need a way to iterate and check for undefined even though the object keys changes dynamically.</p>