error[E0599]: no method named `f` found for unit type `()` in the current scope --> $DIR/shadowed-trait-methods.rs:13:8 | LL | pub trait T { fn f(&self) {} } | - the method is available for `()` here ... LL | ().f() | ^ 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 foo::T; | error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0599`.