A couple of Swift 3 things that I got confused by

explain.swift

import Foundation

// @escape VS @no-escaping
class Uno {
  func closure(completion: () -> Void) {
    // Non-escaping
    completion()

    // Escaping
//    DispatchQueue.main.asyncAfter(deadline: .now() + 5, execute: {
//      completion()
//    })
  }
}

class Dos {
  let uno = Uno()

  func test() {
    uno.closure {
      print("hola!")
    }
  }
}

let dos = Dos()
dos.test()

// Any vs AnyObject
class Tres: NSObject {}
let fiveAsNSNumber:NSNumber = 5
// This is an array of NSObject, everything is tied to a root class, usually NSObject
let anyObjectArray = [Tres(), fiveAsNSNumber]

class Cuatro {}
let fiveAsInt = 5
let fn = { print("closure") }
// This is an array of Any, basically anything can go in here
let anyArray:[Any] = ["a", fiveAsInt, fn, Cuatro()]