Modern C++ Programming Cookbook

Getting ready

The examples in this recipe are based on the variadic function template add() that we wrote in the previous recipe, Writing a function template with a variable number of arguments. That implementation is a left-folding operation. For simplicity, we present the function again:

    template <typename T>     T add(T value)     {       return value;     }     template <typename T, typename... Ts>     T add(T head, Ts... rest)     {       return head + add(rest...);     }