007.swift

class Bucket {
  let id : Int

  init(id: Int) {
    print("\(id) is upon us.")
    self.id = id
  }

  deinit {
    print("\(id) has left the building.")
  }

  func description() -> String {
    return "I am \(id)"
  }
}

func thereBeBuckets() {
  let bb = Bucket(id: 1)
  print(bb.description())
}

func thereBeBucketsLifted() -> (() -> Void) {
  let bb = Bucket(id: 2)

  func sub() {
    let bc = Bucket(id: 3)
    print(bc.description())
    print(bb.description())
  }

  return sub
}

let ba = Bucket(id: 0)
let fn = thereBeBucketsLifted()
thereBeBuckets()

stdout

0 is upon us.
2 is upon us.
1 is upon us.
I am 1
1 has left the building.