| error[E0053]: method `next` has an incompatible type for trait | |
| --> $DIR/issue-21332.rs:5:5 | |
| | | |
| LL | fn next(&mut self) -> Result<i32, i32> { Ok(7) } | |
| | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected enum `std::option::Option`, found enum `std::result::Result` | |
| | | |
| = note: expected type `fn(&mut S) -> std::option::Option<i32>` | |
| found type `fn(&mut S) -> std::result::Result<i32, i32>` | |
| error: aborting due to previous error | |
| For more information about this error, try `rustc --explain E0053`. |