KotlinTips Elvis 快速返回

private fun testElvisReturn(commands: List<String>?) {

    //如果值不符合预期(null)，直接返回

    val firstCommand = commands?.firstOrNull() ?: return



    when(firstCommand) {

        "ADD" -> "Add something"

        "DELETE" -> "Delete something"

        "UPDATE" -> "Update something"

        else -> "Find something"

    }

}