 
 import UIKit
 
-extension Array {
+private extension Array {
   var last: T {
     return self[self.endIndex - 1]
   }

  }
  
  override init(frame: CGRect) {
    super.init(frame: frame)    
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "tagTextChanged:", name: "UITextFieldTextDidChangeNotification", object: self)
    self.layer.borderWidth = BORDER_WIDTH
    self.layer.borderColor = BORDER_COLOR
    self.layer.cornerRadius = CORNER_RADIUS
    self.layer.masksToBounds = true
    self.font = UIFont.systemFontOfSize(FONT_SIZE)
    self.returnKeyType = .Done

  func checkIntersection(sender:TagInput) {
    let typingTag = find(tagArray, sender)
    
    if typingTag==tagArray.last {
      return
    }
    
