Function put_def_kind

crates/ixon/src/proof.rs:264–270

(k: DefKind, buf: &mut Vec<u8>)

      *buf = rest;
      Ok(x)
    },
    None => Err("get_u8: EOF".to_string()),
  }
}

fn compute_mask(flags: &[bool]) -> u64 {
  let mut mask: u64 = 0;
  for (i, &f) in flags.iter().enumerate() {
    if f {
      mask |= 1 << i;