if don’t understand why I have to explicitly do a ...

# announcements

[Stephan Schroeder]

if don’t understand why I have to explicitly do a non-null cast

if (prioritizedViews != null) {
            prioritizedViews as PrioritizedViews<CareHomeView>
        } else ...

in

class CareHomeCombinedView(
    private var prioritizedViews: PrioritizedViews<CareHomeView>? = null
) {

    private val views: PrioritizedViews<CareHomeView> =
        if (prioritizedViews != null) {
            prioritizedViews as PrioritizedViews<CareHomeView>
        } else {
            PrioritizedViews(              
            )
        }
}

class PrioritizedViews<T>(
    vararg viewsByPriority: T?
)

interface CareHomeView {}

the type inference normally includes the null-check! What is different this time?
Here the link to the playground: https://pl.kotl.in/js_ASkwV9

[Dias]

like the error message says by the time following line are executed prioritizedViews can become null again

[Stephan Schroeder]

indeed, making the prioritizedViews a val fixes it!

[adamd]

In general, using `val`s instead of `var`s make Kotlin a lot easier to use 😉