Error return in Switch using enumeration and associated error value

gistfile1.txt

import Cocoa

enum Result {
	case Success
	case Failure(NSError)
}

func DoTask() -> Result {
	return .Failure(NSError.errorWithDomain("Domain", code: 4, userInfo:nil))
}

let result = DoTask()

switch result {
	case let .Failure(error):
		println(error)
	case .Success:
		println("Success")
}