Enum data_encoding::BitOrder

pub enum BitOrder {
    MostSignificantFirst,
    LeastSignificantFirst,
}

Order in which bits are read from a byte

Examples

In the following example, we can see that a base with the MostSignificantFirst bit-order has the most significant bit first in the encoded output. In particular, the output is in the same order as the bits in the byte. The opposite happens with the LeastSignificantFirst bit-order. The least significant bit is first and the output is in the reverse order.

use data_encoding::Builder;
let mut builder = Builder::new(b"01");
let msb = builder.no_pad().unwrap();
let lsb = builder.least_significant_bit_first().no_pad().unwrap();
assert_eq!(msb.encode(&[0b01010011]), "01010011");
assert_eq!(lsb.encode(&[0b01010011]), "11001010");

Variants

MostSignificantFirst

Most significant bit first

This is the most common and most intuitive bit-order. In particular, this is the bit-order used by RFC4648 and thus the usual hexadecimal, base64, base32, base64url, and base32hex encodings. This is the default bit-order when building a base.

LeastSignificantFirst

Least significant bit first

Examples

Here is how one would implement the DNSCurve base32 encoding:

use data_encoding::Builder;
let dns_curve = Builder::new(b"0123456789bcdfghjklmnpqrstuvwxyz")
    .translate(b"BCDFGHJKLMNPQRSTUVWXYZ", b"bcdfghjklmnpqrstuvwxyz")
    .least_significant_bit_first().no_pad().unwrap();
assert_eq!(dns_curve.encode(&[0x64, 0x88]), "4321");
assert_eq!(dns_curve.decode(b"4321").unwrap(), vec![0x64, 0x88]);

Trait Implementations

impl Debug for BitOrder

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Copy for BitOrder

impl Clone for BitOrder

fn clone(&self) -> BitOrder

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl PartialEq for BitOrder

fn eq(&self, __arg_0: &BitOrder) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl Eq for BitOrder