error[E0369]: binary operation `*` cannot be applied to type `Thing` --> $DIR/issue-3820.rs:14:13 | LL | let w = u * 3; //~ ERROR binary operation `*` cannot be applied to type `Thing` | ^^^^^ | = note: an implementation of `std::ops::Mul` might be missing for `Thing` error: aborting due to previous error For more information about this error, try `rustc --explain E0369`.