title: Conform to Protocol and Keep Property Private
body: <p>I need to use a protocol property in the conforming class as a private. But the compiler refuses that. How can I implement that?</p>
  
  <pre><code>protocol ProtocolX: class {
      var x: Int { get set }
  
      func performAnyActionOnX()
  }
  
  extension ProtocolX {
      func performAnyActionOnX() {
          x = 5
          print(x)
      }
  }
  
  class A: ProtocolX {
      private var x:Int = 7
  }
  </code></pre>
  
  <p>Thanks.</p>