summaryrefslogtreecommitdiff
path: root/exercises/macros/macros3.rs
blob: e9ef7f3514857936152831d0d043e37a72b76036 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
// macros3.rs
// Make me compile, without taking the macro out of the module! Scroll down for hints :)

// I AM NOT DONE

mod macros {
    macro_rules! my_macro {
        () => {
            println!("Check out my macro!");
        };
    }
}

fn main() {
    my_macro!();
}

















































// In order to use a macro outside of its module, you need to do something
// special to the module to lift the macro out into its parent.








// The same trick also works on "extern crate" statements for crates that have
// exported macros, if you've seen any of those around.