| error[E0308]: mismatched types | |
| --> $DIR/occurs-check.rs:5:9 | |
| | | |
| LL | f = box f; | |
| | ^^^^^ | |
| | | | |
| | cyclic type of infinite size | |
| | help: try using a conversion method: `box f.to_string()` | |
| error: aborting due to previous error | |
| For more information about this error, try `rustc --explain E0308`. |