小编Tho*_*n74的帖子

抱歉举了这个毫无意义的例子。试图简化它，仍然不明白\xe2\x80\x99s发生了什么。以下给了我Variable \'self.greeting\' used before being initialized：

struct MyView: View {\n    @State var greeting: String\n    var length = Measurement<UnitLength>(value: 5, unit: UnitLength.miles)\n    init() {\n        greeting = "Hello, World!" // Variable \'self.greeting\' used before being initialized\n    }\n    var body: some View {\n        Text(greeting)\n    }\n}\n

虽然这工作正常（var length不同；否则相同）：

struct MyView: View {\n    @State var greeting: String\n    var length = 5 // now Int\n    init() {\n        greeting = "Hello, World!"\n    }\n    var body: some View {\n        Text(greeting)\n    }\n}\n …