for i in list {
    looping
}


for i in ℤ[-1:1] {

};

for i in ℤ⁅-1:1:2⁆ if i > 0 {

};

for (k, v) in dict {
    for (i, j) in list {
        looping
    }
}


for (k, mut v) ∈ dict if k > 0 {
    looping
}