#include <iostream>
#include <random>

class ConstantGenerator
{
public:
    ConstantGenerator(double value) : m_value(value) {}
    double min() const { return 0.0; }
    double max() const { return 1.0; }
    double operator()(){ return m_value; }
    using result_type = double;
private:
    double m_value = 0.0;
};

int main()
{
    std::normal_distribution<double> dist{10.0, 1.0};
    ConstantGenerator gen{0.5};
    std::cout << dist(gen);
}