message: bug marc
diff: @@ -220,7 +220,8 @@ template <typename Input_vertex_range>
  void Toplex_map::insert_independent_simplex(const Input_vertex_range &vertex_range){
  for(const Toplex_map::Vertex& v : vertex_range){
  if(!t0.count(v)) t0.emplace(v, Simplex_ptr_set());
  - t0.at(v).emplace(get_key(vertex_range));
  + auto k = get_key(vertex_range);
  + t0.at(v).emplace(k);
  }
  }
  