title: Check for nil values in Dictionary - Swift 3
body: <p>I have converted a XML into a Dictionary and I would like to check first if any of the values is nil. </p>
  
  <p>Is there any alternative to this ugly code (the Dictionary contains 30 key-value pairs):</p>
  
  <pre><code>if (xmlDict["key1" != nil &amp;&amp; xmlDict["key2" != nil &amp;&amp; .... &amp;&amp; xmlDict["key30" != nil) {
       //Do something with these values
  } else {
       //Do not do anything at all with this dictionary
  }
  </code></pre>
  
  <p><strong>[Update]</strong>
  The dictionary has this format (mixed value types):</p>
  
  <pre><code>let futuramaDict = NSArray(contentsOf: xmlFile!) as? [NSDictionary]
  
  futuramaDict {
       "Cartoon" : "Futurama"
       "Length" : 120
       "MainCharacter" : "Philip J. Fry"
       "ClosestFriends" : ["Bender","Leela","Zoidberg"]
       }
  </code></pre>
  
  <p>I left the other key-value pairs so I don't fill the thread with irrelevant content</p>