std::for_each_n

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Example

Run on Compiler Explorer

main: () = {
    vi: std::vector = (1, 2, 3, 4, 5);
    println(vi);
 
    std::for_each_n(vi.begin(), 3, :(inout n) = n *= 2);
    println(vi);
}

println: (v) = {
    (copy count:= v.size())
    for v do (e) {
        std::cout << e;
        count--;
        if count == 0 {
            std::cout << "\n";
        }
        else {
            std::cout << ", ";
        }
    }
}

Output

1, 2, 3, 4, 5
2, 4, 6, 4, 5