1import core/tree
2
3exercise: () -> (ok: bool) ! tree.no_such_node =
4 ok = false
5 value := tree.new()
6 return when tree.length(value) <> 0 or tree.ordinal(tree.id(usize(42))) <> 42
7 _ = tree.get(value, tree.id(usize(0))) else (problem)
8 ok = problem == tree.no_such_node
9 return
10 end
11end exercise
12
13public main: () -> (code: i32) =
14 code = 1
15 ok := exercise() else false
16 if ok then
17 code = 42
18 end if
19end main