You should read that if you want to know more about this exciting future feature of C++:

C++17 Fold Expressions

by Baptiste Wicht

From the article:

C++11 introduced variadic template to the languages. This new feature allows to write template functions and classes taking an arbitrary number of template parameters. This a feature I really like and I already used it quite a lot in my different libraries. Here is a very simple example computing the sum of the parameters:

// Good with variadics
auto old_sum(){
    return 0;
}

template<typename T1, typename... T>
auto old_sum(T1 s, T... ts){
    return s + old_sum(ts...);;
} 

// Better with fold expressions
template<typename... T>
auto fold_sum_1(T... s){
    return (... + s);
}x