code: final boolean biRun(Object r, Object s, Runnable f, BiRun<?, ?> c) {
      Throwable x;
      Object z;
      if (result == null) {
        if ((r instanceof AltResult && (x = ((AltResult) (z = r)).ex) != null)
            || (s instanceof AltResult && (x = ((AltResult) (z = s)).ex) != null))
          completeThrowable(x, z);
        else
          try {
            if (c != null && !c.claim())
              return false;
            f.run();
            completeNull();
          } catch (Throwable ex) {
            completeThrowable(ex);
          }
      }
      return true;
    }
docs: /* ------------- Projected (Ored) BiCompletions --------------