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
|
//@ proc-macro: weird-hygiene.rs
#![feature(stmt_expr_attributes)]
#![feature(proc_macro_hygiene)]
extern crate weird_hygiene;
use weird_hygiene::*;
macro_rules! other {
($tokens:expr) => {
macro_rules! call_it {
($outer_ident:ident) => {
macro_rules! inner {
() => {
$outer_ident;
}
}
}
}
#[derive(WeirdDerive)]
enum MyEnum {
Value = (stringify!($tokens + hidden_ident), 1).1 //~ ERROR cannot find
}
inner!();
}
}
macro_rules! invoke_it {
($token:expr) => {
#[recollect_attr] {
$token;
hidden_ident //~ ERROR cannot find
}
}
}
fn main() {
// `other` and `invoke_it` are both macro_rules! macros,
// so it should be impossible for them to ever see `hidden_ident`,
// even if they invoke a proc macro.
let hidden_ident = "Hello1";
other!(50);
invoke_it!(25);
}
|
