i = 0

for! [1, 2], i =>
    print! i

assert i == 0 # Python: 2

if! True, do!:
    i = "a"
    print! i

assert i == 0 # Python: "a"

flg = !True
while! do! flg, do!:
    i = "b"
    print! i
    flg.invert!()

assert i == 0 # Python: "b"

match! i:
    0 =>
        i = 3
        print! "OK: i = \{i}"
    _ => print! "Unreachable"

assert i == 0 # Python: 3