code: package it.unibz.inf.ontop.iq;
  
  import it.unibz.inf.ontop.iq.exception.QueryNodeTransformationException;
  import it.unibz.inf.ontop.iq.node.ExplicitVariableProjectionNode;
  import it.unibz.inf.ontop.iq.transform.node.HomogeneousQueryNodeTransformer;
  
  public interface LeafIQTree extends IQTree, ExplicitVariableProjectionNode {
  
      @Override
      LeafIQTree getRootNode();
  
      @Override
      LeafIQTree acceptNodeTransformer(HomogeneousQueryNodeTransformer transformer)
              throws QueryNodeTransformationException;
  }
  