subIndex is not implemented for codimensions different than the entity
I believe that this is the offending line: https://gitlab.dune-project.org/extensions/dune-alugrid/-/blob/40f4a8b6ce5dc726c15ad0087f2def8d035d7101/dune/alugrid/common/defaultindexsets.hh#L146
In particular, this fails to me when I use a triangle (2D) entity as argument to search for its vertex (0D) indices in a 3D grid (ALUGrid<3,3>
):
for (std::size_t subEntity = 0; subEntity != 3; ++subEntity)
is.subIndex(e, subEntity, e.codimension + 2);