error[E0050]: method `foo` has 1 parameter but the declaration in trait `Foo::foo` has 2 --> $DIR/E0050.rs:10:12 | LL | fn foo(&self, x: u8) -> bool; | ------------ trait requires 2 parameters ... LL | fn foo(&self) -> bool { true } //~ ERROR E0050 | ^^^^^ expected 2 parameters, found 1 error[E0050]: method `bar` has 1 parameter but the declaration in trait `Foo::bar` has 4 --> $DIR/E0050.rs:11:12 | LL | fn bar(&self, x: u8, y: u8, z: u8); | -------------------------- trait requires 4 parameters ... LL | fn bar(&self) { } //~ ERROR E0050 | ^^^^^ expected 4 parameters, found 1 error[E0050]: method `less` has 4 parameters but the declaration in trait `Foo::less` has 1 --> $DIR/E0050.rs:12:13 | LL | fn less(&self); | ----- trait requires 1 parameter ... LL | fn less(&self, x: u8, y: u8, z: u8) { } //~ ERROR E0050 | ^^^^^^^^^^^^^^^^^^^^^^^^^^ expected 1 parameter, found 4 error: aborting due to 3 previous errors For more information about this error, try `rustc --explain E0050`.