Storyboard.swift

import UIKit

enum Storyboard: String {
    case main
  
    var value: String {
        return self.rawValue.capitalized
    }
}

extension UIStoryboard {

    convenience init(_ name: Storyboard) {
        self.init(name: name.value, bundle: nil)
    }

    func instantiateViewController<T: UIViewController>() -> T {

        if let name = NSStringFromClass(T.self).components(separatedBy: ".").last, let vc = instantiateViewController(withIdentifier: name) as? T {
            return vc
        }

        fatalError("Could not find " + String(describing: T.self))

    }
}

enum Segue: String {
    case showLogin
}

extension UIViewController {

    func perform(segue: Segue) {
        performSegue(withIdentifier: segue.rawValue, sender: nil)
    }
}

extension UIStoryboardSegue {

    func destination<T: UIViewController>(matching segue: Segue, as vc: T.Type) -> T? {
        if identifier != segue.rawValue { return nil }
        if let nav = destination as? UINavigationController {
            return nav.viewControllers.first as? T
        }
        return destination as? T
    }
}