Dynamic Swift Demo Source

gistfile1.txt

//: Playground - noun: a place where people can play

import UIKit

public protocol Maths
{
  func doMath(left: Double, right: Double) -> Double
}

class Addition: NSObject, Maths
{
  func doMath(left: Double, right: Double) -> Double
  {
    return left + right
  }
}

class Multiplication: Maths
{
  let next: AnyObject = Addition()
  
  override func forwardingTarget(for aSelector: Selector!) -> Any?
  {
//    return Addition()
    return next
  }

  func doMath(left: Double, right: Double) -> Double
  {
    return left * right
  }
}


let math: AnyObject = Multiplication()
//math.perform(Selector("doMath::"), with: 40, with: 2)
math.doMath(left: 2, right: 40)