error[E0621]: explicit lifetime required in the type of `x`
  --> $DIR/ex1-return-one-existing-name-if-else-using-impl-3.rs:8:36
   |
LL |   fn foo<'a>(&'a self, x: &i32) -> &i32 {
   |                           ---- help: add explicit lifetime `'a` to the type of `x`: `&'a i32`
LL |
LL |     if true { &self.field } else { x }
   |                                    ^ lifetime `'a` required

error: aborting due to previous error

For more information about this error, try `rustc --explain E0621`.