     
     // MARK: - Private variables
     private var overlay: UIView!
-    
     private var currentNavigationController: UINavigationController? {
         return UIApplication.sharedApplication().windows.first?.rootViewController as? UINavigationController
     }

    
    private func validateCounts<T, U>(a: [T], _ b: [U]) throws {
        if a.count != b.count {
            throw SidebarMenuError.DifferentNumberOfControllersAndMenuElements(controllersCount: a.count, menuElementsCount: b.count)
        }
    }
    


import UIKit

/**
 Struct storing `title`, `textColor` and `backgroundColor`.
 */
public struct MenuElement {

    public var title: String
    public var textColor: UIColor
    public var backgroundColor: UIColor
    
}

public enum SidebarMenuError: ErrorType {
    
    case NumberOfControllersAndMenuElementsAreNotEqual(controllersCount: Int, menuElementsCount: Int)
    
}

