title: Use of unresolved identifier in UITableViewDelegate extension
body: <p>Instead of assigning the view controller as the <code>UITableViewDelegate</code>, I'm trying to reduce the code in the view controller by creating an extension for the <code>UITableViewDelegate</code>. </p>
  
  <p>Why am I getting the error "Use of unresolved identifier companyDetailVC" for the line <code>companyDetailsVC = CompanyDetailsViewController()</code> when that is correct Swift 3 syntax?</p>
  
  <p><strong>Code</strong></p>
  
  <pre><code>extension TableViewDelegate: UITableViewDelegate {
      func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
          companyDetailsVC = CompanyDetailsViewController()
          self.present(companyDetailsVC, animated: true, completion: nil)
      } 
  }
  </code></pre>
  
  <p><strong>Edit:</strong> I'm trying to do this programmatically without storyboard. I created a <code>UITableViewDelegate</code> extension because I'm trying to reduce the code in the View Controller. </p>