class Fruit {
    int something;
    string fruitName;
    ... more fields
}

class Banana extends Fruit {}
class Apple extends Fruite {}

class SplitFruit {
    Collection<Banana> bananas;
    Collection<Apple> apples;
}

void main() {
    Collection<Fruit> fruits = getTruckWithFruit();
    List<FilterFn> filters = listOf( n -> n.fruitName == "banana", n -> true);
    Colleciton<Collectoin<Fruit>> results = Partition(fruits, filters);
    SplitFruit splitFruit = new SplitFruit;
    splitFruit.bananas = results.get(0); // does not work
    splitFruit.apples = results.get(1); // does not work
    
    // use type-safe version splitFruit
}