why doesn't this work?

val defaultHandler: Consumer<in Throwable>? = RxJavaPlugins.getErrorHandler()
checkNotNull(defaultHandler)
defaultHandler.accept(Throwable()) // only safe or non-null asserted calls are allowed on nullable receiver of type...

what's the point in this then:

public inline fun <T:Any> checkNotNull(value: T?, lazyMessage: () -> Any): T {
    contract {
        returns() implies (value != null)
    }

For now you can do this:

val defaultHandler: Consumer<in Throwable> = checkNotNull(RxJavaPlugins.getErrorHandler())

Thanks 😉 that's what I did as well

contracts disabled for now on 1.2 Available by default without flag in 1.3