error[E0599]: no method named `deref` found for reference `&()` in the current scope --> $DIR/shadow.rs:19:11 | LL | x.deref(); | ^^^^^ method not found in `&()` | = help: items from traits can only be used if the trait is in scope help: the following trait is implemented but not in scope; perhaps add a `use` for it: | LL | use std::ops::Deref; | error: aborting due to previous error For more information about this error, try `rustc --explain E0599`.