declare external.Option<T>

declare other.Plain

union Result <T, E>{
    Success: T
    Failure: E
}

struct Holder <T>{
    value: T
}

struct MaybeHolder <T>{
    value: Option<T>
    otherValue: Plain
}

union HasGenericEvent <T>{
    PlainEvent: Plain
    GenericEvent: Option<T>
}