tell_dont_ask__applied.kt

// somewhere in the code
task.closeIfUnclaimed(createdBefore = LocalDate.of(2021, 1, 14))

// task's better API
class Task(
    initialStatus: Status,
    private val createdAt: LocalDate
) {

    var status: Status = initialStatus
        private set

    private val subscribers = mutableListOf<Subscriber>()

    fun add(subscriber: Subscriber) {
        subscribers.add(subscriber)
    }

    fun closeIfUnclaimed(createdBefore: LocalDate): Boolean {
        if (status == Status.NotStarted && createdAt < createdBefore && subscribers.isEmpty()) {
            status = Resolved
            return true
        }

        return false
    }
}