Scala, class using mutable var, update in overriding method

Question

I am having a hard time understanding how to get the following code structure to work.

In Scala I have a class MyClass which inherits from SomeClass<

Answer 1

You can use an early initializer:

case MyClass(...) extends {
  var mutableArray: ArrayBuffer[Int] = ArrayBuffer.fill(5)(0)
} with SomeClass(..) {