rust/src/test/ui/match/match-ref-mut-invariance.nll.stderr

18 lines
797 B
Plaintext
Raw Normal View History

error: lifetime may not live long enough
--> $DIR/match-ref-mut-invariance.rs:10:9
|
LL | impl<'b> S<'b> {
| -- lifetime `'b` defined here
LL | fn bar<'a>(&'a mut self) -> &'a mut &'a i32 {
| -- lifetime `'a` defined here
LL | match self.0 { ref mut x => x }
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ associated function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
2019-10-27 14:39:14 +00:00
|
= help: consider adding the following bound: `'a: 'b`
= note: requirement occurs because of a mutable reference to &i32
= note: mutable references are invariant over their type parameter
= help: see <https://doc.rust-lang.org/nomicon/subtyping.html> for more information about variance
error: aborting due to previous error