 
 	/* cancel */
 
-	func cancel() {
+	public func cancel() {
 		dispatch_block_cancel(block)
 	}
 	

	/* wait */

	/// If optional parameter forSeconds is not provided, use DISPATCH_TIME_FOREVER
	func wait(seconds: Double = 0.0) {
		if seconds != 0.0 {
			let nanoSeconds = Int64(seconds * Double(NSEC_PER_SEC))
			let time = dispatch_time(DISPATCH_TIME_NOW, nanoSeconds)


// MARK: - qos_class_t

public extension qos_class_t {

    // Convenience description of qos_class_t
	// Calculated property
