Nope, you're right, I need to apply the following diff (wrapped in a fn main() {}) to avoid rustc complaining: # diff -up test.rs test.fixed.rs --- te

Nope, you're right, I need to apply the following diff (wrapped in a fn main() {}) to avoid rustc complaining: # diff -up test.rs test.fixed.rs --- test.rs 2022-01-22 16:03:57.302742242 +0100 +++ test.fixed.rs 2022-01-22 16:03:27.766250377 +0100 @@ -2,13 +2,13 @@ fn main() { // pretend that this was passed in on the command line let my_number_string = String::from("42"); // If we just want to bubble up errors - let my_number: u8 = &my_number_string.parse()?; + let my_number: u8 = my_number_string.parse()?; assert_eq!(my_number, 42); // If we might like to panic! - let my_number: u8 = &my_number_string.parse().unwrap(); + let my_number: u8 = my_number_string.parse().unwrap(); assert_eq!(my_number, 42); // If we're a good Rustacean and check for errors before trying to use the data - if let Ok(my_number: u8) = &my_number_string.parse() { + if let Ok(my_number) = my_number_string.parse::<u8>() { assert_eq!(my_number, 42); } }