ranged_int< [](int i) { return i >= 10 && i <= 20; } > example;
ranged_int< [](int i) { return i == 5; } > other;
auto x = other * example;

// generated automatically
decltype(x) = ranged_int< [](int i) { return (i / 5) >= 10 && (i / 5) <= 20; } >;