As much 1.2 only Swift as you can fit on a slide

swift_1_2.swift

class Swift_1_2 {
  static var v = UIView()
  static let d = [ "a" : 1, "b" : 3 ]
  static func bar() {
    let x: Set<Int>
    if let a = d["a"], b = d["b"] where a < b {
      x = [a, b, b-a]
    } else {
      x = []
    }
    (v as! UILabel).text = "Set: \(x)"
  }
}