What I mean, is it possible to somehow do something like this?

```
class Color {
public:
    static constexpr Color BLACK = {0, 0, 0};

    constexpr Color(int r, int g, int b) : r_(r), g_(g), b_(b) {}

private:
    int r_;
    int g_;
    int b_;
};

```

Compilers complain about class `Color` being incomplete when defining `BLACK` constant.