program main
  fn add_one_in_unsafe(value: i32) -> i32
    unsafe
      local let one: i32
        int 1
      binary +
        var value
        var one
  fn main() -> i32
    call add_one_in_unsafe
      int 41
  test "unsafe block returns final value"
    binary =
      call add_one_in_unsafe
        int 4
      int 5
  test "unsafe block can return bool"
    unsafe
      binary =
        call add_one_in_unsafe
          int 1
        int 2
