UIViewControllerInstantiateHelper.swift

import UIKit

extension UIViewController
{
    // Storyboard identifier from class name
    class var storyboardId: String {
        
        var storyboardId = ""
        let components = String(describing: self).components(separatedBy: ".")
        
        if components.count > 0 {
            storyboardId = components.last!
        }
        
        return storyboardId
    }
    /// Instantinate controller with storyboard identifier from class name from storyboard with passed name.
    class func instantiateFromStoryboard(storyboardName: String) -> Self {
        return instantiateFromStoryboardHelper(self, storyboard: UIStoryboard(name: storyboardName, bundle: nil))
    }
    /// Instantinate controller with storyboard identifier from class name from passed storyboard object.
    class func instantiateFromStoryboard(storyboard: UIStoryboard) -> Self {
        return instantiateFromStoryboardHelper(self, storyboard: storyboard)
    }
    /// Instantinate controller with storyboard identifier from class name from storyboard defined in Storyboard enumeration for this controller
    class func instantiateFromStoryboard() -> Self {
        return instantiateFromStoryboardHelper(self, storyboard: self.storyboard)
    }
    
    fileprivate class func instantiateFromStoryboardHelper<T>(_ type: T.Type, storyboard: UIStoryboard) -> T {
        let controller = storyboard.instantiateViewController(withIdentifier: self.storyboardId) as! T
        return controller
    }
}