title: Swift. URL returning nil
body: <p>I am trying to open a website in my app, but for some reason one line keeps returning nil, heres my code:</p>
  
  <pre><code>let url = URL(string: "http://en.wikipedia.org/wiki/\(element.Name)")!
      if #available(iOS 10.0, *) {
          UIApplication.shared.open(url, options: [:], completionHandler: nil)
      } else {
          UIApplication.shared.openURL(url)
      }
  }
  </code></pre>
  
  <p>It's the first line (<code>let url = URL...</code>) that keeps on returning this error:</p>
  
  <blockquote>
    <p>fatal error: unexpectedly found nil while unwrapping an Optional value.</p>
  </blockquote>
  
  <p>What should I do to fix this?</p>