Receive promised e-mail in macOS 10.12+
问题 Previously, I was using the following to discover e-mail meta-data from a drag & dropped e-mail(/-thread) from Mail.app. if let filenames = draggingInfo.namesOfPromisedFilesDropped(atDestination: URL(fileURLWithPath: destinationDir!)) { /// TODO: in future implementation Mail might return multiple filenames here. /// So we will keep this structure to iterate the filenames //var aPaths: [String] = [] //for _ in filenames { if let aPath = pb.string(forType: "com.apple.pasteboard.promised-file