匿名函数
private val startWaiters = mutableListOf<(Boolean) -> Unit>()
//大家都理解的写法
val callbackFunction: (Boolean) -> Unit = { success ->}
startWaiters.add(callbackFunction)
//这种写法是不是就有点懵逼了
startWaiters.add({success->})
//如果上面的理解那下面这个就好理解了
startWaiters += {success:Boolean->}
