Macro impl_byte

macro_rules! impl_byte {
    (
        $(#[$m:meta])*
        $v:vis struct $name:ident($vt:vis $ty:ty);
    ) => { ... };
    (
        $(#[$m:meta])*
        $v:vis struct $name:ident $(<$lifetime:lifetime>)? {
            $(
                $(#[doc = $doc:literal])*
                $(#[ctx = $ctx_hdr:expr])?
                $(#[parse_if = $parse_if_hdr:expr])?
                $vf:vis $field_name:ident: $field_ty:ty
            ),+
            $(,)?
        }
    ) => { ... };
}

Implements byte for a struct.