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kotlinlang

I want to have `class A : B(), C(d)`, where `d` is a property inside `B`. I was assuming that the supertypes are instantiated in order, and so I should have access to `B.d` by the time I need it for the `C` constructor, but I am not sure how to express that. Is this possible?

you can only have a single superclass, how are you calling multiple superconstructors?

Oops, I simplified it too much for the example.
```class A(
 cProvider: () -> C
): B(), C by cProvider()```
I want to modify the above code to add a property of `B` to be an argument  of `cProvider()`. My understanding is that `B` already exists by the time `cProvider()` is called.

I don't think you can. You cannot reference this when using `by`. I assume you wouldn't be able to access super either.

Does an extra constructor help?
```class A private constructor(c: C) : B(c), C by c {
  constructor(cProvider: () -&gt; C) : this(cProvider())
}```

I wanted it the other way around:
```class A private constructor(c: C) : B(), C by c {
  constructor(cProvider: (D) -&gt; C) : this(cProvider(d))
}```
Where `d` is a property inside `B`. With the extra constructor I can indeed express that, as above, but I get an `Cannot access 'd' before the instance has been initialized` error, so it doesn't look doable.

I see, I misunderstood the problem :disappointed:

The `by` is just syntax sugar for normal delegation, so the solution is to do what it does manually.

That indeed worked, thank you. The con is that now I have to manually delegate tens of properties / methods that the single `by` handled before.

<https://youtrack.jetbrains.com/issue/KT-83|https://youtrack.jetbrains.com/issue/KT-83>