error: UnsafeMutablePointer<NSError?>?) -> Bool in guard let label = element as? UILabel else { return false } if label.frame.height <= 44 { error?.pointee = NSError(domain: kGTXErrorDomain, code: 999, userInfo: [ NSLocalizedDescriptionKey: "Suggest label's height is to be at least over 44.0.", kGTXErrorFailingElementKey: element ]) return false } else { return true } }