Module encoding/hex

Hexadecimal encoding and decoding.

Converts between raw bytes (ArrayList(u8)) and hex strings.

Example

hex :: import("std/encoding/hex");

s := hex.encode(data);         // "deadbeef"
b := hex.decode(`deadbeef`).unwrap();

Encoding is lowercase only; decoding accepts either case, and mixed case within one string.

Stability

unstable — two names short of complete, and the missing one is visible in the code. _hex_encode_impl already takes its alphabet as a parameter and _HEX_CHARS is the only value ever passed, so Rust's hex::encode_upper is one export away; that is additive and safe. The name is the part that is not settled: hex_encode / hex_encode_upper repeats the module (D2's module-prefix stutter, listed STILL OPEN for the whole encoding group in plans/STD_API_STABILIZATION.md §4), and the decided direction is hex.encode on the imported module value. Adding a second stuttering name first would mean renaming two instead of one.

hex_decode became Result-returning in #467 (D13) and has not been through a release; its errors are the shared EncodingError, whose own open question — one enum for three codecs, where Rust has hex::FromHexError — is the other thing holding this module unstable, since hex_decode can only ever produce two of that enum's five variants.