Hexadecimal

Hexadecimal text for digests, and back.

Source: runtime/digest/hex.pep

to_hex

to_hex(bytes: u8[]): String

Returns bytes as lowercase hexadecimal text, two digits per byte, the way checksums and git object ids are usually written.

Parameters

• bytes — the bytes to write, such as a digest from finish

Returns

• a String of 2 * bytes.count characters from 0-9a-f

Example

import digest;

assert(digest.to_hex([0, 15, 255]) == "000fff", "two digits per byte");

from_hex

from_hex(text: String): Result<u8[]>

Returns the bytes that hexadecimal text stands for, two digits per byte, the reverse of to_hex. Upper- and lowercase digits are both accepted.

Parameters

• text — hexadecimal text, such as a checksum

Returns

• the bytes, or an error when text has an odd length or a character that is not a hexadecimal digit

Example

import digest;

var bytes = digest.from_hex("000fFF").value();
assert(bytes.count == 3 && bytes[2] == 255, "two digits per byte");
assert(digest.from_hex("abc").is_err(), "an odd length");