Method for_each

highs/util/HighsHashTree.h:1431–1435

  template <typename F>
  auto for_each(F&& f) const
      -> decltype(HighsHashTableEntry<K, V>().forward(f)) {
    using R = decltype(for_each(f));
    return for_each_recurse<R>(root, f);
  }

  HighsHashTree() = default;