Example of layering CoroutineContext

SomeClass.kt

class SomeClass : CoroutineScope {

  val jobA = Job()
  
  override val coroutineContext: CoroutineContext
    get() = jobA + Dispatchers.Main
    
  fun doSomething() {
  
    // create a new coroutine using jobA and Main dispatcher
    launch {
    
      val jobB = Job()
      
      // jobB and Main dispatcher
      launch(jobB) {
      
        // jobB and Default dispatcher
        launch(Default) { }
      }
      
      // jobA and Default dispatcher
      launch(Default) { }
      
      // jobB and Default dispatcher
      launch(jobB + Default) { }
    }
  }
}