| //@ 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)); |
| } |
