rust/src/test/run-pass/hygienic-labels-in-let.rs
2015-01-30 04:38:54 +01:00

77 lines
1.6 KiB
Rust

// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// ignore-pretty: pprust doesn't print hygiene output
macro_rules! loop_x {
($e: expr) => {
// $e shouldn't be able to interact with this 'x
'x: loop { $e }
}
}
macro_rules! while_true {
($e: expr) => {
// $e shouldn't be able to interact with this 'x
'x: while 1 + 1 == 2 { $e }
}
}
macro_rules! run_once {
($e: expr) => {
// ditto
'x: for _ in 0..1 { $e }
}
}
pub fn main() {
let mut i = 0;
let j: int = {
'x: loop {
// this 'x should refer to the outer loop, lexically
loop_x!(break 'x);
i += 1;
}
i + 1
};
assert_eq!(j, 1);
let k: int = {
'x: for _ in 0..1 {
// ditto
loop_x!(break 'x);
i += 1;
}
i + 1
};
assert_eq!(k, 1);
let l: int = {
'x: for _ in 0..1 {
// ditto
while_true!(break 'x);
i += 1;
}
i + 1
};
assert_eq!(l, 1);
let n: int = {
'x: for _ in 0..1 {
// ditto
run_once!(continue 'x);
i += 1;
}
i + 1
};
assert_eq!(n, 1);
}