Function find_unary 

pub(crate) fn find_unary<R>(
    reader: &mut R,
    queue_value: &mut u8,
    queue_bits: &mut u32,
    leading_bits: impl Fn(u8) -> u32,
    max_bits: impl Fn(&mut u32) -> u32,
    checked_shift: impl Fn(u8, u32) -> Option<u8>,
) -> Result<u32>
where
    R: Read,