gistfile1.cpp

  ...
        const std::array<float32_t, 2> bounds;

    private:
        static std::array<float32_t, 2> compute_bounds(const std::vector<Component>& components)
        {
            std::array<float32_t, 2> bounds = {0, 0};
            for (const auto& component: components)
            {
                bounds[0] -= component.multiplier;
                bounds[1] += component.multiplier;
            }
            bounds[0] = 0.5 * (1 + bounds[0]);
            bounds[1] = 0.5 * (1 + bounds[1]);
            return bounds;
        }
    public:
        template <typename N, typename C>
        FractalNoise(N&& noise,
                     C&& components):
            noise(std::forward<N>(noise))
            components(std::forward<C>(components)),
            bounds(compute_bounds(this->components))  // <--- HERE
        {
        }
...