error[E0308]: mismatched types --> $DIR/pattern-tyvar.rs:15:18 | LL | Bar::T1(_, Some::(x)) => { //~ ERROR mismatched types | ^^^^^^^^^^^^^^^^ expected struct `std::vec::Vec`, found isize | = note: expected type `std::option::Option>` found type `std::option::Option` error: aborting due to previous error For more information about this error, try `rustc --explain E0308`.