How to Convert Between Enums and Integers in Rust

Use the From and Into traits to convert between enums and integers safely and idiomatically. Implement From<u8> for your enum to convert integers to variants, and From<YourEnum> to convert variants back to integers.

#[derive(Debug)]
enum Status { Ok = 0, Error = 1 }

impl From<u8> for Status {
    fn from(value: u8) -> Self {
        match value {
            0 => Status::Ok,
            1 => Status::Error,
            _ => panic!("Invalid status"),
        }
    }
}

impl From<Status> for u8 {
    fn from(status: Status) -> Self {
        match status {
            Status::Ok => 0,
            Status::Error => 1,
        }
    }
}

fn main() {
    let s: Status = 0u8.into();
    let i: u8 = s.into();
}

Converting between Enums and Integers in Rust lets you treat your custom list of options as simple numbers and back again. It is like having a menu where you can order by the item name or by its number on the list. You use this when saving data to a file or sending it over a network where numbers are more efficient than text.