@available(iOS 11.0, *)
struct T {}
@propertyWrapper
struct Wrapper<Value> {
var wrappedValue: Value
}
struct Test {
@available(iOS 11.0, *)
@Wrapper var a: T // this is ok
@available(iOS 11.0, *)
@Wrapper<T> var b: T // 'T' is only available in iOS 11.0 or newer
}
what is the difference between a
and b
?