Encoding

std.encoding provides binary-to-text encoders and decoders. The current public modules are encoding.base64, encoding.base64url, and encoding.hex. String-returning encoders return owned String throws(AllocError), so callers use try or catch.

import std.encoding;

fn main() {
    let padded = try encoding.base64.encode("fo");
    let compact = try encoding.base64.encode_no_pad("fo");
    let direct = try encoding.base64.encode("Hello");

    assert padded.str() == "Zm8=";
    assert compact.str() == "Zm8";
    assert direct.str() == "SGVsbG8=";
}

encoding.base64 uses the standard alphabet with + and /.

Method	Purpose
base64.encode(data)	Encode with = padding.
base64.encode_no_pad(data)	Encode without padding.

Both methods use canonical bytes.Bytes inputs. Callers can pass string literals, String, existing byte views, or [u8] slices directly as call arguments.

encoding.base64url uses the URL-safe alphabet with - and _.

import std.encoding;

fn main() {
    let url = try encoding.base64url.encode_no_pad("hello?");
    assert url.str() == "aGVsbG8_";
}

Method	Purpose
base64url.encode(data)	Encode with URL-safe alphabet and = padding.
base64url.encode_no_pad(data)	Encode with URL-safe alphabet and no padding.

For local namespace imports, import the submodule directly:

import std.encoding.base64;

fn main() {
    let text = try base64.encode("Hello");
    assert text.str() == "SGVsbG8=";
}

encoding.hex provides lowercase and uppercase hex encoding plus strict decoding.

import std.encoding;
import std.encoding.hex;

fn main() {
    let lower = try encoding.hex.encode("Az");
    let upper = try hex.encode_upper("Az");
    let decoded = try hex.decode("486900");
    let bytes = decoded.slice();

    assert lower.str() == "417a";
    assert upper.str() == "417A";
    assert bytes.length == 3;
    assert bytes[2] == 0 as u8;
}

Method	Purpose
hex.valid(text)	Return whether a string is valid even-length hex.
hex.encoded_length(len)	Return the byte length of encoded hex output.
hex.decoded_length(text)	Return decoded byte length or HexError.Invalid.
hex.encode(data)	Encode lowercase hex into String throws(AllocError).
hex.encode_upper(data)	Encode uppercase hex into String throws(AllocError).
hex.encode_into(data, out)	Encode lowercase hex into caller-owned bytes.
hex.encode_upper_into(data, out)	Encode uppercase hex into caller-owned bytes.
hex.decode(text)	Decode strict hex into Array<u8> throws(HexError | AllocError).
hex.decode_into(text, out)	Decode strict hex into caller-owned bytes.

Malformed hex raises HexError.Invalid. _into calls raise HexError.Buffer when the output slice is too small.