Derive Macro ledger_proto::DecodeOwned

#[derive(DecodeOwned)]
{
    // Attributes available to this derive:
    #[encdec]
}

#[derive(DecodeOwned)] support.

generates a [DecodeOwned][encdec_base::decode::DecodeOwned] implementation equivalent to calling .decode() on each field in order.

for example:

#[derive(Debug, PartialEq)]
struct Something {
    a: u8,
    b: u16,
    c: [u8; 3],
}

// `#[derive(Decode)]` equivalent implementation
impl DecodeOwned for Something {
  type Output = Something;
  type Error = Error;

  fn decode_owned(buff: &[u8]) -> Result<(Self::Output, usize), Self::Error> {
    let mut index = 0;

    let a = buff[0];
    index += 1;

    let b = buff[1] as u16 | (buff[2] as u16) << 8;
    index += 2;

    let mut c = [0u8; 3];
    c.copy_from_slice(&buff[3..][..3]);
    index += 3;

    Ok((Self{a, b, c}, index))
  }
}