Convenience functions for ObjectIdentifier hashes

ObjectIdentifier.swift

/// Generate a unique identifier for an AnyObject.
/// 2nd slowest. Converts to String.
public func obid (object: AnyObject) -> String {
  return "\(obid(object) as Int)"
}

/// Generate a unique identifier for an AnyObject.
/// Fastest. Every other function relies on this one.
public func obid (object: AnyObject) -> Int {
  return ObjectIdentifier(object).hashValue
}

/// Generate a unique identifier for an AnyObject.
/// Slowest. Checks for nil and converts to String.
public func obid (object: AnyObject!) -> String {
  return "\(obid(object) as Int)"
}

/// Generate a unique identifier for an AnyObject.
/// 2nd fastest. Checks for nil.
public func obid (object: AnyObject!) -> Int {
  return object != nil ? obid(object!) : 0
}

Playground.playground

func measure (n: Int, fn: () -> ()) {
//  return
  let start = CFAbsoluteTimeGetCurrent()
  for i in 0...n {
    fn()
  }
  println(CFAbsoluteTimeGetCurrent() - start)
}

let n = 100

let view = UIView()

measure(n) {
  let view: UIView = UIView()
  let id: Int = obid(view)
}

measure(n) {
  let view: UIView = UIView()
  let id: String = obid(view)
}

measure(n) {
  let view: UIView! = UIView()
  let id: Int = obid(view)
}

measure(n) {
  let view: UIView! = UIView()
  let id: String = obid(view)
}