std::ranges::fold_right_last

Example

main: () = {
    ai: std::array = (1, 2, 3, 4, 5, 6, 7, 8);
    vs: std::vector<std::string> = ("A", "B", "C", "D");

    r1:= std::ranges::fold_right_last(ai.begin(), ai.end(), std::plus<>());
    std::cout << "r1: (r1*)$\n";

    r2:= std::ranges::fold_right_last(vs, std::plus<>());
    std::cout << "r2: (r2*)$\n";

    // Use a program defined function object (lambda-expression):
    r3:= std::ranges::fold_right_last(ai, :(x: int, y: int) x + y + 99);
    std::cout << "r3: (r3*)$\n";

    // Get the product of the std::pair::second of all pairs in the vector:
    CharFloat: type == std::pair<char, float>;
    data: std::vector = (
        :CharFloat=('A', 3.f),
        :CharFloat=('B', 3.5f),
        :CharFloat=('C', 4.f));
    r4:= std::ranges::fold_right_last
    (
        data | std::ranges::views::values, std::multiplies<>()
    );
    std::cout << "r4: (r4*)$\n";
}

Output

r1: 36
r2: ABCD
r3: 729
r4: 42.000000