title: CustomStringConvertible in enum
body: <p>I have following enum in a class.</p>
  
  <pre><code>enum Attributes: String, CustomStringConvertible {
      case eventDate
      case eventName
      case eventType
      case country
  
      var description: String {
          return self.rawValue
      }
  }
  </code></pre>
  
  <p>When I try have the following code, compiler complains with following error.</p>
  
  <pre><code>var attributesList: [String] {
      return [
          Attributes.eventDate, //&lt;-- Compiler error on this row
          Attributes.eventName,
          Attributes.eventType,
          Attributes.country]
  }
  </code></pre>
  
  <blockquote>
    <p>Cannot convert value of the type 'Attributes' to expected element type 'String'</p>
  </blockquote>
  
  <p>Shouldn't the "CustomStringConvertible" protocol return the "description"?
  What is wrong in the above code?</p>