code: @Override
      @SuppressWarnings("unchecked")
      public <D, App extends Applicative<?, App>, TravB extends Traversable<D, Choice3<A, B, ?>>,
              AppB extends Applicative<D, App>,
              AppTrav extends Applicative<TravB, App>> AppTrav traverse(Function<? super C, ? extends AppB> fn,
                                                                        Function<? super TravB, ? extends AppTrav> pure) {
          return match(a -> pure.apply((TravB) Choice3.<A, B, D>a(a)).coerce(),
                       b -> pure.apply((TravB) Choice3.<A, B, D>b(b)).coerce(),
                       c -> fn.apply(c).<Choice3<A, B, D>>fmap(Choice3::c).<TravB>fmap(Functor::coerce).coerce());
      }
docs: {@inheritDoc}