Feedback on Error Handling

[beephsupreme]

I'm trying to wrap my head around errors, results, match, ?, and so forth. The code seems to work, mostly, but I feel like I'm missing something.

Not sure why I need to n.unwrap() on line 30 in order to println! on line 31.

Any feedback would be appreciated.

Code is at rust_error_handling/main.rs at main · beephsupreme/rust_error_handling · GitHub

[H2CO3]

@beephsupreme

Not sure why I need to n.unwrap() on line 30 in order to println! on line 31

Because n is the return value of get_int(), which has type Result<usize, MyError>. Your match is a no-op in the Ok case, since you throw away its value. You probably wanted to assign it to a variable.

[quinedot]

E.g.

fn main() {
    let n = match get_int() {
        Ok(n) => n,
        Err(e) => panic!("{}: {}", e, "Could not get n"),
    };

    println!("{}", n);
}

match doesn't modify things in place. But it is an expression that can "return" a value for you to assign.