Add constant/magic value

[apbr]

Add the possibility to define some values as constant/magic values.
Such a value is always the same. It can't be changed in the constructor and also has no setter.

Possible syntax:

#[bitsize(13)]
struct Register {
    header: u4,
    body: u7,
   #[magic(Code::Error)]
    code: Code,
}

#[bitsize(2)]
#[derive(FromBits)]
enum Code { Success, Error, IoError, GoodExample }

[hecatia-elegua]

There are various concepts called magic number.
File header magic numbers could be excluded when parsing.
If the number is needed afterwards, like in your example supposedly, it would just need a fixed value for code and read-only values I think.

[apbr]

If the number is needed afterwards, like in your example supposedly, it would just need a fixed value for code and read-only values I think.

Yes, that's what I am looking for, so is this already possible with bilge?