Function hex_nibble

datafusion/spark/src/function/math/unhex.rs:73–80

(c: u8)

#[inline]
fn hex_nibble(c: u8) -> Option<u8> {
    match c {
        b'0'..=b'9' => Some(c - b'0'),
        b'a'..=b'f' => Some(c - b'a' + 10),
        b'A'..=b'F' => Some(c - b'A' + 10),
        _ => None,
    }
}

/// Decodes a hex-encoded byte slice into binary data.
/// Returns `true` if decoding succeeded, `false` if the input contains invalid hex characters.