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// Copyright 2013 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.
// check that the derived impls for the comparison traits shortcircuit
// where possible, by having a type that fails when compared as the
// second element, so this passes iff the instances shortcircuit.
pub struct FailCmp;
impl PartialEq for FailCmp {
fn eq(&self, _: &FailCmp) -> bool { fail!("eq") }
}
impl PartialOrd for FailCmp {
fn lt(&self, _: &FailCmp) -> bool { fail!("lt") }
}
impl Eq for FailCmp {}
impl Ord for FailCmp {
fn cmp(&self, _: &FailCmp) -> Ordering { fail!("cmp") }
}
#[deriving(PartialEq,PartialOrd,Eq,Ord)]
struct ShortCircuit {
x: int,
y: FailCmp
}
pub fn main() {
let a = ShortCircuit { x: 1, y: FailCmp };
let b = ShortCircuit { x: 2, y: FailCmp };
assert!(a != b);
assert!(a < b);
assert_eq!(a.cmp(&b), ::std::cmp::Less);
}
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