1$ cat hello.🔥
 2def main():
 3    print("hello world")
 4    for x in range(9, 0, -3):
 5        print(x)
 6$ mojo hello.🔥
 7hello world
 89
 96
103
11$

 1def your_function(a, b):
 2    let c = a
 3    # Uncomment to see an error:
 4    # c = b  # error: c is immutable
 5
 6    if c != b:
 7        let d = b
 8        print(d)
 9
10your_function(2, 3)

1def sort(v: ArraySlice[Int]):
2  for i in range(len(v)):
3    for j in range(len(v) - i - 1):
4      if v[j] > v[j + 1]:
5        swap(v[j], v[j + 1])

1struct MyPair:
2  var first: Int
3  var second: F32
4
5  def __init__(self, first: Int, second: F32):
6    self.first = first
7    self.second = second

 1struct HeapArray:
 2    var data: Pointer[Int]
 3    var size: Int
 4    var cap: Int
 5
 6    fn __init__(self&):
 7        self.cap = 16
 8        self.size = 0
 9        self.data = Pointer[Int].alloc(self.cap)
10
11    fn __init__(self&, size: Int, val: Int):
12        self.cap = size * 2
13        self.size = size
14        self.data = Pointer[Int].alloc(self.cap)
15        for i in range(self.size):
16            self.data.store(i, val)
17
18    fn __copyinit__(self&, other: Self):
19        self.cap = other.cap
20        self.size = other.size
21        self.data = Pointer[Int].alloc(self.cap)
22        for i in range(self.size):
23            self.data.store(i, other.data.load(i))
24
25    fn __del__(owned self):
26        self.data.free()
27
28    fn dump(self):
29        print_no_newline("[")
30        for i in range(self.size):
31            if i > 0:
32                print_no_newline(", ")
33            print_no_newline(self.data.load(i))
34        print("]")