hexponent 0.3.1

pub(crate) fn hex_digit_to_int(digit: u8) -> Option<u8> {
    match digit {
        b'0' => Some(0x0),
        b'1' => Some(0x1),
        b'2' => Some(0x2),
        b'3' => Some(0x3),
        b'4' => Some(0x4),
        b'5' => Some(0x5),
        b'6' => Some(0x6),
        b'7' => Some(0x7),
        b'8' => Some(0x8),
        b'9' => Some(0x9),
        b'a' | b'A' => Some(0xa),
        b'b' | b'B' => Some(0xb),
        b'c' | b'C' => Some(0xc),
        b'd' | b'D' => Some(0xd),
        b'e' | b'E' => Some(0xe),
        b'f' | b'F' => Some(0xf),
        _ => None,
    }
}

pub(crate) fn consume_hex_digits(data: &[u8]) -> (&[u8], &[u8]) {
    let i = data
        .iter()
        .position(|&b| hex_digit_to_int(b).is_none())
        .unwrap_or_else(|| data.len());

    data.split_at(i)
}