Is there a better way to handle the failure case?

Better way to return failure?

class Box<A> {
  public let value: A
  init(_ value: A) { self.value = value }
}

enum Result<A> {
  case Success(Box<A>)
  case Failure(NSError)
}

class Fizz {
}

class Buzz {
}

class Foo {
  func foo() -> Result<Fizz> {
    let result = // a result
    return result
  }
}

class Bar {
  func bar(foo: Foo) -> Result<Buzz> {
    switch foo.foo() {
      case .Success(let fizzBox):
        let buzz = // a buzz
        return .Success(Box(buzz))
      // There must be a swiftier way to handle the failure case!
      case .Failure(let error):
        return .Failure(error)
    }
  }
}

https://twitter.com/cocoaphony/status/568791893917732865