message: VectorTree: inherit ContainerProxy members using macro
diff: @@ -182,62 +182,8 @@ class VectorTree {
  public:
  using typename Base::container_type;
  - // Sequence Container interface
  -
  - using typename Base::value_type;
  -
  - using typename Base::const_reference;
  - using typename Base::reference;
  -
  - using typename Base::const_iterator;
  - using typename Base::iterator;
  -
  - using typename Base::difference_type;
  - using typename Base::size_type;
  -
  - using typename Base::const_reverse_iterator;
  - using typename Base::reverse_iterator;
  -
  - using Base::begin;
  - using Base::cbegin;
  - using Base::cend;
  - using Base::end;
  -
  - using Base::crbegin;
  - using Base::crend;
  - using Base::rbegin;
  - using Base::rend;
  -
  - using Base::back;
  - using Base::front;
  - using Base::operator[];
  - using Base::at;
  -
  - using Base::empty;
  - using Base::max_size;
  - using Base::size;
  -
  - using Base::emplace_back;
  - using Base::push_back;
  -
  - using Base::emplace_front;
  - using Base::push_front;
  -
  - using Base::emplace;
  - using Base::insert;
  -
  - using Base::clear;
  - using Base::erase;
  - using Base::pop_back;
  - using Base::pop_front;
  -
  - using Base::assign;
  - using Base::operator=;
  - using Base::swap;
  -
  - using Base::capacity;
  - using Base::reserve;
  - using Base::resize;
  + // Import (via `using`) ContainerProxy members supported by std::vector.
  + USING_CONTAINER_PROXY_STD_VECTOR_MEMBERS(Base)
  // Move-cast to wrapped container's type. Moves out the container.
  explicit operator container_type() && { return std::move(container_); }
  