$ cargo run Compiling structs v0.1.0 (file:///projects/structs) error[E0106]: missing lifetime specifier --> src/main.rs:3:15 | 3 | username: &str, | ^ expected named lifetime parameter | help: consider introducing a named lifetime parameter | 1 ~ struct User<'a> { 2 | active: bool, 3 ~ username: &'a str, | error[E0106]: missing lifetime specifier --> src/main.rs:4:12 | 4 | email: &str, | ^ expected named lifetime parameter | help: consider introducing a named lifetime parameter | 1 ~ struct User<'a> { 2 | active: bool, 3 | username: &str, 4 ~ email: &'a str, | For more information about this error, try `rustc --explain E0106`. error: could not compile `structs` due to 2 previous errors