message: [terminal] Size: Adds operator+=(Coordinate rhs)
diff: @@ -29,6 +29,13 @@ constexpr Coordinate operator+(Coordinate a, Coordinate b) noexcept
  return Coordinate{a.row + b.row, a.column + b.column};
  }
  +constexpr Coordinate& operator+=(Coordinate& a, Coordinate b) noexcept
  +{
  + a.row += b.row;
  + a.column += b.column;
  + return a;
  +}
  +
  constexpr void swap(Coordinate& a, Coordinate& b) noexcept
  {
  Coordinate const c = a;
  