fn small_tuple_ext<S: ReadStream, C: ElemCompose>(s: &mut S, c: &mut C)-> ParseResult {
tuple(s.read_u8()? as u32, s, c)
}
fn large_tuple_ext<S: ReadStream, C: ElemCompose>(s: &mut S, c: &mut C)-> ParseResult {
tuple(s.read_u32()?, s, c)
}
fn tuple<S: ReadStream, C: ElemCompose>(n: u32, s: &mut S, c: &mut C) -> ParseResult {
c.open("tuple");
create_list(n, c, &mut || parse_any(s, c))?;
c.close();
Ok(())
}