src/test/run-pass/hygiene.rs

   1 // Copyright 2016 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![allow(unused)]
  12
  13 fn f() {
  14     let x = 0;
  15     macro_rules! foo { () => {
  16         assert_eq!(x, 0);
  17     } }
  18
  19     let x = 1;
  20     foo!();
  21 }
  22
  23 fn g() {
  24     let x = 0;
  25     macro_rules! m { ($x:ident) => {
  26         macro_rules! m2 { () => { ($x, x) } }
  27         let x = 1;
  28         macro_rules! m3 { () => { ($x, x) } }
  29     } }
  30
  31     let x = 2;
  32     m!(x);
  33
  34     let x = 3;
  35     assert_eq!(m2!(), (2, 0));
  36     assert_eq!(m3!(), (2, 1));
  37
  38     let x = 4;
  39     m!(x);
  40     assert_eq!(m2!(), (4, 0));
  41     assert_eq!(m3!(), (4, 1));
  42 }
  43
  44 mod foo {
  45     macro_rules! m {
  46         ($f:ident : |$x:ident| $e:expr) => {
  47             pub fn $f() -> (i32, i32) {
  48                 let x = 0;
  49                 let $x = 1;
  50                 (x, $e)
  51             }
  52         }
  53     }
  54
  55     m!(f: |x| x + 10);
  56 }
  57
  58 fn interpolated_pattern() {
  59     let x = 0;
  60     macro_rules! m {
  61         ($p:pat, $e:expr) => {
  62             let $p = 1;
  63             assert_eq!((x, $e), (0, 1));
  64         }
  65     }
  66
  67     m!(x, x);
  68 }
  69
  70 fn patterns_in_macro_generated_macros() {
  71     let x = 0;
  72     macro_rules! m {
  73         ($a:expr, $b:expr) => {
  74             assert_eq!(x, 0);
  75             let x = $a;
  76             macro_rules! n {
  77                 () => {
  78                     (x, $b)
  79                 }
  80             }
  81         }
  82     }
  83
  84     let x = 1;
  85     m!(2, x);
  86
  87     let x = 3;
  88     assert_eq!(n!(), (2, 1));
  89 }
  90
  91 fn match_hygiene() {
  92     let x = 0;
  93
  94     macro_rules! m {
  95         ($p:pat, $e:expr) => {
  96             for result in &[Ok(1), Err(1)] {
  97                 match *result {
  98                     $p => { assert_eq!(($e, x), (1, 0)); }
  99                     Err(x) => { assert_eq!(($e, x), (2, 1)); }
 100                 }
 101             }
 102         }
 103     }
 104
 105     let x = 2;
 106     m!(Ok(x), x);
 107 }
 108
 109 fn label_hygiene() {
 110     'a: loop {
 111         macro_rules! m { () => { break 'a; } }
 112         m!();
 113     }
 114 }
 115
 116 fn main() {
 117     f();
 118     g();
 119     assert_eq!(foo::f(), (0, 11));
 120     interpolated_pattern();
 121     patterns_in_macro_generated_macros();
 122     match_hygiene();
 123 }