cond = True
s = if cond:
    do "then block"
    do "else block"
assert s == "then block"

if! cond:
    do!:
        print! "then block!"
    do!:
        print! "else block!"

a = 1
_ = match a:
    (_: {1}) -> 1
    (_: 0..1) -> 100
    (i: Int) -> i
    (s: Str) -> 1
    _ -> panic "unknown object"

for! 0..<10, i =>
    print! "i = \{i}"

counter = !10
print! counter
while! do!(not(counter == 0)), do!:
    print! "counter = \{counter}"
    counter.dec!()

x = 1
Del x