error[E0214]: parenthesized type parameters may only be used with a `Fn` trait --> $DIR/issue-23589.rs:2:12 | LL | let v: Vec(&str) = vec!['1', '2']; | ^^^^^^^^^ | | | only `Fn` traits may use parentheses | help: use angle brackets instead: `Vec<&str>` error[E0308]: mismatched types --> $DIR/issue-23589.rs:2:29 | LL | let v: Vec(&str) = vec!['1', '2']; | ^^^ expected `&str`, found `char` | help: if you meant to write a `str` literal, use double quotes | LL | let v: Vec(&str) = vec!["1", '2']; | ~~~ error: aborting due to 2 previous errors Some errors have detailed explanations: E0214, E0308. For more information about an error, try `rustc --explain E0214`.