Starting a coroutine with launch

When your objective is to start a coroutine that doesn't return a result, you should use launch(). It's designed for fire-and-forget scenarios where you only want to be notified if the computation fails, and it still provides you with a function to cancel it if needed. Consider this example:

fun main(args: Array<String>) = runBlocking {
  val task = launch {
    doSomething()
  }
  task.join()
  println("completed")
}

Here, doSomething() throws an exception:

fun doSomething() {
  throw UnsupportedOperationException("Can't do")
}

The exception will be printed to the stack as expected, but notice that the execution was not interrupted and the application finished the execution of main():