code: public int addAll(KTypeContainer<? extends KType> container) {
      ensureCapacity(container.size());
      return addAll((Iterable<? extends KTypeCursor<? extends KType>>) container);
    }
docs: Adds all elements from the given {@link KTypeContainer} to this set.
  
  @return Returns the number of elements actually added as a result of this
  call (not previously present in the set).