message: Code review : find_child implementation improvement
diff: @@ -1189,11 +1189,16 @@ class Simplex_tree {
  * Returns null_simplex() if it does not exist
  */
  Simplex_handle find_child(Simplex_handle sh, Vertex_handle vh) {
  - std::vector<Vertex_handle> child = {vh};
  - for (auto vertex : simplex_vertex_range(sh)) {
  - child.push_back(vertex);
  - }
  - return find(child);
  + if (!has_children(sh))
  + return null_simplex();
  +
  + Simplex_handle child = sh->second.children()->find(vh);
  + // Specific case of boost::flat_map does not find, returns boost::flat_map::end()
  + // in simplex tree we want a null_simplex()
  + if (child == sh->second.children()->members().end())
  + return null_simplex();
  +
  + return child;
  }
  public:
  