56 lines
1.4 KiB
Rust
56 lines
1.4 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.
|
|
|
|
macro_rules! loop_x {
|
|
($e: expr) => {
|
|
// $e shouldn't be able to interact with this 'x
|
|
'x: loop { $e }
|
|
}
|
|
}
|
|
|
|
macro_rules! run_once {
|
|
($e: expr) => {
|
|
// ditto
|
|
'x: for _ in 0..1 { $e }
|
|
}
|
|
}
|
|
|
|
macro_rules! while_x {
|
|
($e: expr) => {
|
|
// ditto
|
|
'x: while 1 + 1 == 2 { $e }
|
|
}
|
|
}
|
|
|
|
pub fn main() {
|
|
'x: for _ in 0..1 {
|
|
// this 'x should refer to the outer loop, lexically
|
|
loop_x!(break 'x);
|
|
panic!("break doesn't act hygienically inside for loop");
|
|
}
|
|
|
|
'x: loop {
|
|
// ditto
|
|
loop_x!(break 'x);
|
|
panic!("break doesn't act hygienically inside infinite loop");
|
|
}
|
|
|
|
'x: while 1 + 1 == 2 {
|
|
while_x!(break 'x);
|
|
panic!("break doesn't act hygienically inside infinite while loop");
|
|
}
|
|
|
|
'x: for _ in 0..1 {
|
|
// ditto
|
|
run_once!(continue 'x);
|
|
panic!("continue doesn't act hygienically inside for loop");
|
|
}
|
|
}
|