std::generate

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Example

Run on Compiler Explorer

i: int = 0;

f: () -> int = {
    return i++;
}

main: () = {
    v:= std::vector<int>(5);

    std::generate(v.begin(), v.end(), f);
    std::println("v: {}", v);

    // Initialize with default values 0,1,2,3,4 from a lambda function
    // Equivalent to std::iota(v.begin(), v.end(), 0);
    n: int = 0;
    std::generate(v.begin(), v.end(), :() -> int = {
        val:= n$;
        n$++;
        return val;
    });
    std::println("v: {}", v);
}

Output

v: [1, 2, 3, 4, 5]
v: [0, 1, 2, 3, 4]