Compile error in Swift 4 on parameter passing
问题 I used 3rd party library in Xcode 9 Beta 3. And I am getting the following error in the completion call, I am not able to resolve this error: DispatchQueue.main.asyncAfter(deadline: .now() + delay) { self.animationView?.alpha = 0 self.containerView.alpha = 1 completion?() // -> Error: Missing argument parameter #1 in call. } And getting the following warning in the completion function: func openAnimation(_ completion: ((Void) -> Void)?) { // -> Warning: When calling this function in Swift 4