address.swift

// before

func formattedAddress() -> String {
  let lines:NSMutableArray = NSMutableArray(capacity: 4)
  let zipStateCityArgs:NSMutableArray = NSMutableArray(capacity: 3)

  let zip = self.stringValueForKeyPath("address_zip")
  let city = self.stringValueForKeyPath("address_city")
  let state = self.stringValueForKeyPath("address_state")
  for arg in [zip, city, state] {
    if arg != nil {
      zipStateCityArgs.addObject(arg!)
    }
  }

  let line1 = self.stringValueForKeyPath("address_line1")
  let line2 = self.stringValueForKeyPath("address_line2")
  let zipStateCity = zipStateCityArgs.componentsJoinedByString(", ")
  let country = self.stringValueForKeyPath("address_country")
  
  for line in [line1, line2, zipStateCity, country] {
    if line != nil && !(line!.isEmpty) {
      lines.addObject(line!)
    }
  }
  
  return lines.componentsJoinedByString("\n")
}

// after

public var displayName: String {
  let zipStateCity = [postalCode, city, state].reduce("") { (a, r) -> String in
    if let component = r {
      return (a == "") ? component : "\(a), \(component)"
    }
    return a
  }
  return [line1, line2, zipStateCity, country].reduce("") { (a, r) -> String in
    if let line = r {
      return (a == "") ? line : "\(a)\n\(line)"
    }
    return a
  }
}