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//@ run-pass
// check that the derived impls for the comparison traits shortcircuit
// where possible, by having a type that panics when compared as the
// second element, so this passes iff the instances shortcircuit.
use std::cmp::Ordering;
pub struct FailCmp;
impl PartialEq for FailCmp {
fn eq(&self, _: &FailCmp) -> bool { panic!("eq") }
}
impl PartialOrd for FailCmp {
fn partial_cmp(&self, _: &FailCmp) -> Option<Ordering> { panic!("partial_cmp") }
}
impl Eq for FailCmp {}
impl Ord for FailCmp {
fn cmp(&self, _: &FailCmp) -> Ordering { panic!("cmp") }
}
#[derive(PartialEq,PartialOrd,Eq,Ord)]
struct ShortCircuit {
x: isize,
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::Ordering::Less);
}
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