extern fn printf(fmt: str, ...): i32 = {};
fn println(value: i32) = {
printf("%d\n", value);
}
fn while_loop(end: i32): i32 = {
let mut index = 0;
while (index < end) = {
println(index);
index = index + 1;
};
return index;
}
fn main() = {
let end = 10;
let index = while_loop(end);
println(index);
}