std::ranges::replace, std::ranges::replace_if

Example

print_seq: (v) = {
    for v do (e) {
        std::cout << "(e)$ ";
    }
    std::cout << '\n';
}

main: () = {
    ranges: namespace == std::ranges;

    p: std::array = (1, 6, 1, 6, 1, 6);
    print_seq(p);
    ranges::replace(p, 6, 9);
    print_seq(p);

    q: std::array = (1, 2, 3, 6, 7, 8, 4, 5);
    print_seq(q);
    ranges::replace_if(q, :(x: int) x > 5, 5);
    print_seq(q);

    nums: std::array = (
        :std::complex<double>=(1, 3),
        :std::complex<double>=(1, 3));
    print_seq(nums);
    ranges::replace(nums, std::complex<double>(1, 3), std::complex<double>(4, 1));
    print_seq(nums);
}

Output

1 6 1 6 1 6 
1 9 1 9 1 9 
1 2 3 6 7 8 4 5 
1 2 3 5 5 5 4 5 
(1,3) (1,3) 
(4,1) (4,1) 