@inkandswitch/bijou128

bijou128_wasm

JS/Wasm bindings for bijou128 — a canonical, length-prefixed varint encoding for u128 (1–17 bytes per value).

The wider sibling of bijou64_wasm. Same API shape (free functions, JS bigint boundary), wider integer range.

Build

bodge:128   # nix dev-shell command; output lands in dist/

Usage

import { encode, decode, decodeAll, encodedLen, MAX_BYTES } from "bijou128";

encode(500n);                                  // Uint8Array([0xF1, 0x00, 0x04])
decode(new Uint8Array([0xF1, 0x00, 0x04]));    // { value: 500n, bytesRead: 3 }
decodeAll(buf);                                // Array<bigint> of every value in buf
encodedLen(500n);                              // 3
MAX_BYTES();                                   // 17

u128 crosses the boundary as JS bigint. Unlike bijou64's decodeAll (which returns a typed BigUint64Array), bijou128.decodeAll returns a plain Array<bigint> — there is no BigUint128Array in the web platform, and we don't want to silently truncate at the 64-bit mark.

Subpath imports

Beyond the default entry, the package exposes a few subpaths:

• bijou128/slim — bring-your-own init. Import this and call initSync({ module: ... }) yourself; nothing auto-loads the wasm. See the wasm-bodge slim docs.
• bijou128/debug — same API, but backed by an unoptimized wasm with DWARF preserved, so Chrome DevTools can step through Rust source. Much larger; use only while debugging. A bijou128/debug/slim variant exists too.
• bijou128/wasm and bijou128/wasm-base64 — the raw .wasm and a base64-inlined module, for custom loaders.
• bijou128/iife — a classic <script>-tag build exposing a global.

License

Dual MIT / Apache-2.0.