error[E0308]: mismatched types --> $DIR/param-mismatch-no-names.rs:4:20 | LL | same_type([x], Some(y)); | --------- --- ^^^^^^^ expected `[X; 1]`, found `Option` | | | | | expected all arguments to be this `[X; 1]` type because they need to match the type of this parameter | arguments to this function are incorrect | = note: expected array `[X; 1]` found enum `Option` note: function defined here --> $DIR/param-mismatch-no-names.rs:1:4 | LL | fn same_type(_: T, _: T) {} | ^^^^^^^^^ - ---- ---- this parameter needs to match the `[X; 1]` type of parameter #1 | | | | | parameter #2 needs to match the `[X; 1]` type of this parameter | parameter #1 and parameter #2 both reference this parameter `T` error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0308`.