title: NSAttributedString has no member replacingOccurrences error
body: <p>This is my code </p>
  
  <pre><code>class AmDocViewController: UIViewController,UITextViewDelegate {
      var text1:String!
      let replaceYName: String = "text1"
  
      var textA:String!
      let replaceFName: String = "textA"
  
      var textB:String!
      let replaceyGFName: String = "textB"
  
      @IBOutlet weak var myTextView: UITextView!
  override func viewDidLoad() {
          super.viewDidLoad()
          myTextView.delegate = self;
          self.view.endEditing(true)
  
   let notes37 = NSAttributedString(string:"""
  (SOME SAMPLE TEXT......)
  """, attributes:[NSAttributedStringKey.foregroundColor: UIColor.gray])
  
   let newMutableString77 = notes37.mutableCopy() as! NSMutableAttributedString
          newMutableString77.append(notes37)
  
  myTextView.attributedText = newMutableString77 as NSAttributedString
  
          let originalString = myTextView.text
  
          let updatedString = originalString?.replacingOccurrences(of: replaceYName, with: text1)
          let updatedString1 = updatedString?.replacingOccurrences(of: replaceFName, with: textA)
  
          if textB == "" {
              let updatedString2 = updatedString1?.replacingOccurrences(of: str25, with: "N/A")
          }
          if textB != ""{
              let updatedString2 = updatedString1?.replacingOccurrences(of: replaceyGFName, with: textB)
          }
  
          myTextView.text = updatedString2
  
          myTextView.textAlignment = NSTextAlignment.center
      }
  </code></pre>
  
  <p>Getting below error message in the if statement lines</p>
  
  <pre><code>Argument type 'NSAttributedString' does not conform to expected type 'StringProtocol'
  </code></pre>
  
  <p>Please advice how to use the String value received from other ViewController TextField(text1) and replace a attributed String in a TextView ?</p>