Swift. URL returning nil : <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>
