title: [NSObject : AnyObject]?' does not have a member named 'subscript' in Xcode 6 Beta 6
body: <p>I am building an app in Xcode 6 Beta 6 in Swift and I keep getting this error:</p>
  
  <pre><code>[NSObject : AnyObject]?' does not have a member named 'subscript'
  </code></pre>
  
  <p>I have no idea how to fix this. I have tried looking at this <a href="https://stackoverflow.com/questions/25381338/nsobject-anyobject-does-not-have-a-member-named-subscript-error-in-xcode">[NSObject : AnyObject]?&#39; does not have a member named &#39;subscript&#39; error in Xcode 6 beta 6</a> but I still don't understand how that solves the problem. If someone could explain that to me, that would be very nice. If you want to see my code, here it is:</p>
  
  <pre><code>import UIKit
  
  class TimelineTableViewController: UITableViewController {
  
   override func viewDidAppear(animated: Bool) {
  
      if ((PFUser.currentUser()) != nil) {
  
          //Create an UIAlertController if there isn't an user
          var loginAlert:UIAlertController = UIAlertController(title: "Sign Up/ Log In", message: "Please sign up or log in", preferredStyle: UIAlertControllerStyle.Alert)
  
          //Add a textView in the Log In Alert for the username
          loginAlert.addTextFieldWithConfigurationHandler({
              textfield in
              textfield.placeholder = "Your Username"
          })
  
          //Add a textView in the Log In Alert for the password
          loginAlert.addTextFieldWithConfigurationHandler({
              textfield in
              textfield.placeholder = "Your Password"
              textfield.secureTextEntry = true
          })
  
          //Place the user-input into an array and set the username and password accordingly for Log In
          loginAlert.addAction(UIAlertAction(title: "Login", style: UIAlertActionStyle.Default, handler: {
              alertAction in
              let textFields:NSArray = loginAlert.textFields as NSArray
              let usernameTextfield:UITextField = textFields.objectAtIndex(0) as UITextField
              let passwordTextfield:UITextField = textFields.objectAtIndex(1) as UITextField
  
              PFUser.logInWithUsernameInBackground(usernameTextfield.text, password: passwordTextfield.text){
                  (user:PFUser!, error:NSError!)-&gt;Void in
                  if ((user) != nil){
                      println("Login successfull")
                  }else{
                      println("Login failed")
                  }
  
  
              }
  
          }))
  
          //Place the user-input into an array and set the username and password accordingly for Sign Up
          loginAlert.addAction(UIAlertAction(title: "Sign Up", style: UIAlertActionStyle.Default, handler: {
              alertAction in
              let textFields:NSArray = loginAlert.textFields as NSArray
              let usernameTextfield:UITextField = textFields.objectAtIndex(0) as UITextField
              let passwordTextfield:UITextField = textFields.objectAtIndex(1) as UITextField
  
              var sweeter:PFUser = PFUser()
              sweeter.username = usernameTextfield.text
              sweeter.password = passwordTextfield.text
  
              sweeter.signUpInBackgroundWithBlock{
                  (success:Bool!, error:NSError!)-&gt;Void in
                  if !(error != nil){
                      println("Sign Up successfull")
                  }else{
                      let errorString = error.userInfo["error"] as NSString
                      println(errorString)
                  }
  
  
              }
  
          }))
      }
  }
  
  override func viewDidLoad() {
      super.viewDidLoad()
  
      // Uncomment the following line to preserve selection between presentations
      // self.clearsSelectionOnViewWillAppear = false
  
      // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
      // self.navigationItem.rightBarButtonItem = self.editButtonItem()
  }
  
  override func didReceiveMemoryWarning() {
      super.didReceiveMemoryWarning()
      // Dispose of any resources that can be recreated.
  }
  </code></pre>
  
  <p>Here is where the error is occuring:</p>
  
  <p><img src="https://i.stack.imgur.com/JKdx8.png" alt="enter image description here"></p>
  
  <p>Please tell me why this is occurring. Thanks!</p>