Common interface for Flux/Mono that defines common operators about reactor-core HOT 2 CLOSED

1. If you have Common b = a.map(v -> v), JIT has harder time to figure out what the actual type will be and if a call-site switches implementation, you may end up with megamorphic dispatches. A concrete type will yield concrete binding.

2. Doesn't really work in Java because we can't define higher order generic types such as U<T> where U can also change. Otherwise, the moment there is a change in the type argument, you need an ? extends Common<T>:

interface Common<T> {
   <R extends Common<T>> R filter(Predicate<T> predicate);
   <R extends Common<U>> U map(Function<T, U> mapper);
}

Returning variant types is discouraged and forces one to have target typing steps, otherwise one looses specifics:

   Common<Integer> c = Flux.range(1, 10);

   c.map(v -> v).filter(v -> true).elementAt(1);

   Flux<Integer> f = c.map(v -> v).filter(v -> true);
   Flux<Integer> g =f.elementAt(1);

Interestingly, those who want to split Publisher into subtypes based on numbers later want to "abstract" them back into one single type.

from reactor-core.

Closing for now, @akarnokd point is valid, we can revisit the issue post 2.5 eventually after some more wave of feedbacks :)

from reactor-core.