- index_set_cell (her->get_elt_property ("heads"), LEFT, new_head_drul[LEFT]->self_scm_ );
- index_set_cell (her->get_elt_property ("heads"), RIGHT, new_head_drul[RIGHT]->self_scm_ );
+ index_set_cell (her->get_elt_property ("heads"), LEFT, new_head_drul[LEFT]->self_scm () );
+ index_set_cell (her->get_elt_property ("heads"), RIGHT, new_head_drul[RIGHT]->self_scm () );