is there a not so verbose way to define a class that contain kotlinlang #announcements

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)

Jonathan Mew

04/30/2019, 12:39 PM

is the class you want to add to

open

iex

04/30/2019, 12:39 PM

I can make it open yes

Jonathan Mew

04/30/2019, 12:41 PM

is extension too verbose?

open class A {}

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

iex

04/30/2019, 12:41 PM

my problem with verbosity is when

has a few fields

then you have to list them all in the constructor of B and pass to

A()

as well

Jonathan Mew

04/30/2019, 12:42 PM

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

iex

04/30/2019, 12:42 PM

also, ideally

should be a data class...

(and

as well. I could also model both as case classes from a sealed class)

(and put the common fields in the sealed class)

Jonathan Mew

04/30/2019, 12:45 PM

hmmm does B want to be a data class also?

spand

04/30/2019, 12:45 PM

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 ?

iex

04/30/2019, 12:46 PM

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

as now the fields would have to be declared in

Notification

and then again in the default notification class...

Jonathan Mew

04/30/2019, 12:47 PM

data class A(val field: Any)

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

but then awkward to grab the internal fields 😞

iex

04/30/2019, 12:47 PM

in the later A and B aren't related though

I need to be able to match

Jonathan Mew

04/30/2019, 12:48 PM

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

👍 1

iex

04/30/2019, 12:48 PM

yeah was thinking that too. Will try it out

thank you!

Jonathan Mew

04/30/2019, 12:48 PM

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

iex

04/30/2019, 12:48 PM

I doubt that there's anything else 😄

spand

04/30/2019, 12:48 PM

Either that or relax the requirement that

NotificationWithProgress

needs to be a

Notification

also and just pass it manually

iex

04/30/2019, 12:49 PM

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

considering a function that accept these notifications as parameters

and matches on them

ok... trying out the delegate

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