error[E0107]: function takes 1 generic argument but 2 generic arguments were supplied --> $DIR/explicit-generic-args-for-impl.rs:4:5 | LL | foo::("".to_string()); | ^^^ ------ help: remove this generic argument | | | expected 1 generic argument | note: function defined here, with 1 generic parameter: `T` --> $DIR/explicit-generic-args-for-impl.rs:1:4 | LL | fn foo(_f: impl AsRef) {} | ^^^ - = note: `impl Trait` cannot be explicitly specified as a generic argument error: aborting due to previous error For more information about this error, try `rustc --explain E0107`.