message: Code review: constify find_child and for instead of while loop
diff: @@ -1124,9 +1124,8 @@ class Simplex_tree {
  return;
  // Reverse loop starting before the last one for 'next' to be the last one
  for (auto simplex = siblings->members().rbegin() + 1; simplex != siblings->members().rend(); simplex++) {
  - auto next = siblings->members().rbegin();
  std::vector<std::pair<Vertex_handle, Node> > intersection;
  - while(next != simplex) {
  + for(auto next = siblings->members().rbegin(); next != simplex; next++) {
  bool to_be_inserted = true;
  Filtration_value filt = simplex->second.filtration();
  // If all the boundaries are present, 'next' needs to be inserted
  @@ -1141,8 +1140,6 @@ class Simplex_tree {
  if (to_be_inserted) {
  intersection.emplace_back(next->first, Node(nullptr, filt));
  }
  - // loop until simplex is reached
  - next++;
  }
  if (intersection.size() != 0) {
  // Reverse the order to insert
  @@ -1183,7 +1180,7 @@ class Simplex_tree {
  * Vertex_handle.
  * Returns null_simplex() if it does not exist
  */
  - Simplex_handle find_child(Simplex_handle sh, Vertex_handle vh) {
  + Simplex_handle find_child(Simplex_handle sh, Vertex_handle vh) const {
  if (!has_children(sh))
  return null_simplex();
  