void PM_io_parser<PMDEC>::debug_hedge(Halfedge_handle e) const
{
  out << index(e)
      << "(" << index(source(e)) << "," << index(target(e)) << ") "
      << index(face(e)) << " " << index(twin(e))
      << " ["<< mark(e) << "]" <<" "<<&*(face(e)) << std::endl;
}
void PM_io_parser<PMDEC>::debug_hedge(Halfedge_handle e) const
{
  out << index(e)
      << "(" << index(source(e)) << "," << index(target(e)) << ") "
      << index(face(e)) << " " << index(twin(e))
      << " ["<< mark(e) << "]" <<" "<<&*(face(e)) << std::endl;
}