Found solution without additional map: ```fun dumm...

# announcements

[Czar]

Found solution without additional map:

fun dummy(input: List<Any>): Stream<SomeSpecificType> =
         input.parallelStream().map {
             when {
                 it is String -> SomeSpecificType(it)
                 else -> {
                    performActionWhichReturnsBoolean(it)
                    null
                 }
             }
         }.filter(Objects::nonNull)