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//@ run-pass
//
// At one time, the `==` operator (and other binary operators) did not
// support subtyping during type checking, and would therefore require
// LHS and RHS to be exactly identical--i.e. to have the same lifetimes.
//
// This was fixed in 1a7fb7dc78439a704f024609ce3dc0beb1386552.
#[derive(Copy, Clone)]
struct Input<'a> {
foo: &'a u32
}
impl <'a> std::cmp::PartialEq<Input<'a>> for Input<'a> {
fn eq(&self, other: &Input<'a>) -> bool {
self.foo == other.foo
}
fn ne(&self, other: &Input<'a>) -> bool {
self.foo != other.foo
}
}
fn check_equal<'a, 'b>(x: Input<'a>, y: Input<'b>) -> bool {
// Type checking error due to 'a != 'b prior to 1a7fb7dc78
x == y
}
fn main() {
let i = 1u32;
let j = 1u32;
let k = 2u32;
let input_i = Input { foo: &i };
let input_j = Input { foo: &j };
let input_k = Input { foo: &k };
assert!(check_equal(input_i, input_i));
assert!(check_equal(input_i, input_j));
assert!(!check_equal(input_i, input_k));
}
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