Swift 4.0 でこんな変更が必要ぽいのだけど、これって SE-0110 Distinguish between single-tuple and multiple-argument function types https://github.com/apple/swift-evolution/blob/master/proposals/0110-distingish-single-tuple-arg.md の影響なのかな？

 func run(_ options: NoOptions<SourceKittenError>) -> Result<(), SourceKittenError> { print(version) - return .success() + return .success(()) }

swift-evolution - This maintains proposals for changes and user-visible enhancements to the Swift Programming Language.