Failable conversion?

[ianthetechie]

Hey, thanks for the great crate!

It would be neat if there was a failable version, for cases when an enumeration with an integral repr doesn't use the full range (some bit patterns are invalid). I'm not sure if this fits within the goals of the crate, but thought I'd open the feature request anyways.

[wrenger]

Apologies for the delayed response. So you are looking for getters that return a result?

enum MyEnum {
    A = 1,
    B = 2,
    // others are not valid
}

#[bitfield(u8)]
struct Bitfield {
    #[bits(4)]
    my_data: MyEnum,
    #[bits(4)]
    other: u8,
}

assert_eq!(Ok(MyEnum::B), Bitfield(0xffff_0002).my_data_checked());
assert!(Bitfield(0xffff_ffff).my_data_checked().is_err());