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kotlinlang

is there a not so verbose way to define a class that contains all the fields from another + a new one (I don't care if it's via inheritance, composition)

is extension too verbose?
```
open class A {}

class B(val a: Any): A()```

my problem with verbosity is when `A` has a few fields

then you have to list them all in the constructor of B and pass to `A()` as well

sure, if they need passing in, they need passing in somewhere..

also, ideally `A` should be a data class...

(and `B` as well. I could also model both as case classes from a sealed class)

(and put the common fields in the sealed class)

hmmm does B want to be a data class also?

```
interface Notitication
interface ProgressNotification : Notification { 
val extra: Any
}

data class WithProgress(override val extra: Any, private val notification: Notification) : ProgressNotification, Notification by notification
```

Something like this ?

crossed my mind too, but I think that it doesn't help with verbosity... :see_no_evil:

as now the fields would have to be declared in `Notification` and then again in the default notification class...

```data class A(val field: Any)

data class B(val a: A, val otherField: Any)```

but then awkward to grab the internal fields :disappointed:

in the later A and B aren't related though

I think the interface/delegation is probably your best bet.

yeah was thinking that too. Will try it out

but maybe someone more Kotlin-literate will have a better suggestion!

I doubt that there's anything else :smile:

Either that or relax the requirement that `NotificationWithProgress` needs to be a `Notification` also and just pass it manually

yeah but then my notification parameter would have to be an "any"?

considering a function that accept these notifications as parameters