docs: protected Collection<AbstractElement> getElementsToParse(AbstractElement root,
  			List<AbstractElement> handledUnorderedGroupElements) {
  		if (root instanceof UnorderedGroup) {
  			if (handledUnorderedGroupElements.isEmpty())
  				return ((CompoundElement) root).getElements();
  			List<AbstractElement> result = Lists.newArrayList(root);
  			for (AbstractElement child : ((UnorderedGroup) root).getElements()) {
  				if (!handledUnorderedGroupElements.contains(child)) {
  					result.add(child);
  				}
  			}
  			return result;
  		}
  		return getElementsToParse(root);
  	}