title: How to use regular expressions in Swift 3?
body: <p>I wanted to follow <a href="https://www.raywenderlich.com/86205/nsregularexpression-swift-tutorial" rel="noreferrer">this tutorial</a> to learn about <code>NSRegularExpression</code> in <code>Swift</code>, but it has not been updated to <code>Swift 3</code>. When I open the playground with the examples they provide, I get several errors being one of them the call:</p>
  
  <pre><code>let regex = NSRegularExpression(pattern: pattern, options: .allZeros, error: nil)
  </code></pre>
  
  <p>I've seen that now that initializer throws an exception so I changed the call, but that <code>.allZeros</code> does not seem to exist anymore. I don't find any tutorial or example with an equivalent of that in <code>Swift 3</code>, could somebody tell me what option should now replace such <code>.allZeros</code> option?</p>