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kotlinlang

Is there a way to specify that a container that implements `List` has a subtype that contains elements that are a subtype of the elements of the parent?

```interface A
class AImpl : A

interface Container : List<A>
class ContainerImpl : Container, List<AImpl> {
    // …
}```
I'm getting:
```Type parameter 'E' of 'interface List<out E> : Collection<E>' has inconsistent values: A, AImpl.```
I know I can do:
```interface Container<T> : List<T>
class ContainerImpl : Container<AImpl> {
    // …
}```
but it doesn't make sense for `Container` to be parameterized in my case.

<https://youtrack.jetbrains.com/issue/KT-9438>

This is the closest you can get probably:
```interface A
class AImpl : A

typealias Container = ContainerT&lt;*&gt;
interface ContainerT&lt;out T: A&gt; : List&lt;T&gt;
class ContainerImpl : ContainerT&lt;AImpl&gt;```

Yeah that's what I'm thinking of. But since it's a core type of the library, it's going to be confusing to users still.