SwiftyButton.swift

extension UIControl.Event: Hashable{
    public var hashValue: Int{
        return Int(self.rawValue)
    }
    
    static func == (lhs: UIControl.Event, rhs: UIControl.Event) -> Bool{
        return lhs.rawValue == rhs.rawValue
    }
}

class Button: UIButton{
    
    private class Actuator{
        let action: ()->Void
        
        init(action: @escaping ()->Void){
            self.action = action
        }
        
        @objc func performAction(){
            action()
        }
    }
    
    private var actions = [UIControl.Event:Actuator]()
    
    func on(_ event: UIControl.Event, perform action: @escaping ()->Void){
        actions[event] = Actuator(action: action)
        addTarget(actions[event], action: #selector(Actuator.performAction), for: event)
    }
}