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How to declare anonymous mixin using type parameter in Scala

Some questions were asked that are somewhat related to this problem, but they do not seem to be true.

I use the Cake pattern to shift the Storage system into production code and the stub storage system for testing. This is cool, but there is a class created in the original class, which should also have a mixed stub storage system. Since it is hidden inside the implementation, I do not have access to it.

Everything looks like this:

class Main { this: Storage =>
  ...
  val used = Used(...)
  ...
}

class Used { this: Storage =>
  ...
}

When testing "Used," I just new Used with StubStorageleave. I did the same with Main, but before that, he used Used. Now that I am Maincreating a naive instance Used, I have this problem.

:

class Main[T <: Storage] { this: T =>
  ...
  val used = Used[T](...)
  ...
}

class Used[T <: Storage] { this: T =>
  ...
}
object Used {
  def apply[T <: Storage](...) = new Used(...) with T
}

, , , T. ? , , , OO , - .

Factory, mixins.

: , .:) , , :

trait UsedProvider {
  def createUsed = Used.apply _
}

class Main { this: Storage with UsedProvider =>
  val used = createUsed(...)
}

: new Main with StubStorage with StubUsedProvider.

+3
1

, Main used, ?

abstract class Main { this: Storage =>
  val s = "s"
  val used: Used
}

:

val main = new Main with StubStorage { val used = new Used(s) with StubStorage }
0

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