src/test/ui/rust-2021/reserved-prefixes.rs

   1 // compile-flags: -Z unstable-options --edition 2021
   2
   3 macro_rules! demo2 {
   4     ( $a:tt $b:tt ) => { println!("two tokens") };
   5 }
   6
   7 macro_rules! demo3 {
   8     ( $a:tt $b:tt $c:tt ) => { println!("three tokens") };
   9 }
  10
  11 macro_rules! demo4 {
  12     ( $a:tt $b:tt $c:tt $d:tt ) => { println!("four tokens") };
  13 }
  14
  15 fn main() {
  16     demo3!(foo#bar);   //~ ERROR prefix `foo` is unknown
  17     demo2!(foo"bar");  //~ ERROR prefix `foo` is unknown
  18     demo2!(foo'b');    //~ ERROR prefix `foo` is unknown
  19
  20     demo2!(foo'b);     //~ ERROR prefix `foo` is unknown
  21     demo3!(foo# bar);  //~ ERROR prefix `foo` is unknown
  22     demo4!(foo#! bar); //~ ERROR prefix `foo` is unknown
  23     demo4!(foo## bar); //~ ERROR prefix `foo` is unknown
  24
  25     demo4!(foo#bar#);
  26     //~^ ERROR prefix `foo` is unknown
  27     //~| ERROR prefix `bar` is unknown
  28
  29     demo3!(foo # bar);
  30     demo3!(foo #bar);
  31     demo4!(foo!#bar);
  32     demo4!(foo ##bar);
  33
  34     demo3!(r"foo"#bar);
  35     demo3!(r#foo#bar);
  36 }