CppCoreGuidelines Enum.2 使用枚举来表示一组相关的常量

enum class Web_color { red = 0xFF0000, green = 0x00FF00, blue = 0x0000FF };

enum class Product_info { red = 0, purple = 1, blue = 2 };

void print(Product_info inf)
{
    switch (inf) {
    case Product_info::red: cout << "red"; break;
    case Product_info::purple: cout << "purple"; break;
    }
}

int main()
{
    auto info = Product_info::red;
    print(info);
}