title: Unnecessary escape character warning
body: <p>This shows a warning of <code>Unnecessary escape character</code>. how do I resolve this.</p>
  
  <pre><code>    validateEmail = email =&gt; {
          var re = /^(([^&lt;&gt;()\[\]\\.,;:\s@"]+(\.[^&lt;&gt;()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
          return re.test(String(email).toLowerCase());
      };
  </code></pre>