src/test/ui/macros/macro-pat.rs

   1 // run-pass
   2
   3 macro_rules! mypat {
   4     () => (
   5         Some('y')
   6     )
   7 }
   8
   9 macro_rules! char_x {
  10     () => (
  11         'x'
  12     )
  13 }
  14
  15 macro_rules! some {
  16     ($x:pat) => (
  17         Some($x)
  18     )
  19 }
  20
  21 macro_rules! indirect {
  22     () => (
  23         some!(char_x!())
  24     )
  25 }
  26
  27 macro_rules! ident_pat {
  28     ($x:ident) => (
  29         $x
  30     )
  31 }
  32
  33 fn f(c: Option<char>) -> usize {
  34     match c {
  35         Some('x') => 1,
  36         mypat!() => 2,
  37         _ => 3,
  38     }
  39 }
  40
  41 pub fn main() {
  42     assert_eq!(1, f(Some('x')));
  43     assert_eq!(2, f(Some('y')));
  44     assert_eq!(3, f(None));
  45
  46     assert_eq!(1, match Some('x') {
  47         Some(char_x!()) => 1,
  48         _ => 2,
  49     });
  50
  51     assert_eq!(1, match Some('x') {
  52         some!(char_x!()) => 1,
  53         _ => 2,
  54     });
  55
  56     assert_eq!(1, match Some('x') {
  57         indirect!() => 1,
  58         _ => 2,
  59     });
  60
  61     assert_eq!(3, {
  62         let ident_pat!(x) = 2;
  63         x+1
  64     });
  65 }