Hi! Why is this OK ``` rebookingList.filter { ...

# announcements

[Can Orhan]

Hi! Why is this OK

rebookingList.filter {
        val data = it.data
        when (data) {
            is AccountFeedItem<*> -> {
                data.data is FeedItemTreatment
            }
            else -> false
        }
    }

But this isn't?

rebookingList.filter {
        when (it.data) {
            is AccountFeedItem<*> -> {
                it.data.data is FeedItemTreatment
            }
            else -> false
        }
    }

[diesieben07]

The compiler cannot be sure that it.data is not subject to change, so it will not smart-cast

[Can Orhan]

Ahh of course! Thank you 🙂

[igor.wojda]

@Can Orhan to be specific in 2nd example other thread may change data BTW I think that in Kotlin 1.3 you will be able to do this when (val data = it.data)