在swift assert（0）中不能将Int类型的值转换为预期的参数类型Bool

Question

I am translating objective -C to swift, but I get error when I write assert(0) in swift, the error message is "in swift assert(0) Cannot convert value of type Int to expected argument type Bool "

my code in objective -c:

switch ([[UIApplication sharedApplication] applicationState]) {
        case UIApplicationStateActive:
            [statusStr appendString:@"foreground"];
            break;
        case UIApplicationStateInactive:
            [statusStr appendString:@"inactive"];
            break;


        case UIApplicationStateBackground:
            [statusStr appendString:@"background"];
            break;

        default:
            assert(0);
            break;
    }

and translate in swift :

 switch UIApplication.shared.applicationState {

            case .active:
                statusStr += "foreground"
            case .inactive:
                statusStr += "inactive"
            case .background:
                statusStr += "background"
            default:
                assert(0)
                break

            }

I don't know 0 mean in swift make it assert(true) or assert(false) .

Thanks in advance.

Answer 1

由于OC弱类型语言，它可以自动将0转换为false，因此在assert中可以运行，但是swift是强类型语言，因此您应该使用assert（false）或自己翻译