Why does runSubscriptionOn() loose type information for Uni<Void>

[samodadela]

Hi,

Can you explain why the return type is Uni<Object> instead of Uni<Void>?

        Uni<Object> uni = Uni.createFrom().item(
                () -> {
                    runBlocking();
                    return null;
                })
            .runSubscriptionOn(managedExecutor);

It works fine, with a Boolean, for example.

        Uni<Boolean> uni = Uni.createFrom().item(
                () -> {
                    runBlocking();
                    return true;
                })
            .runSubscriptionOn(managedExecutor);

Thanks.

[jponge]

This is how Java generics work with a lambda returning null, the compiler assumes Object in absence of any other type hint in its surrounding context.

You could give a hint to void: Uni.createFrom().<Void>item(...)

[gavinking]

public static final Void nil = null;

...

Uni<Void> uni = Uni.createFrom().item(
      () -> {
          runBlocking();
          return nil;
      })
  .runSubscriptionOn(managedExecutor);

[jponge]

Excellent!

[samodadela]

Thanks!
Nice solution. Maybe nil could become UNI_NULL someday.