MaxGraey / as-bignum

Work in progress

WebAssembly fixed length big numbers written on AssemblyScript

Provide wide numeric types such as u128, u256, i128, i256 and fixed points and also its arithmetic operations.

Namespace safe contain equivalents with overflow/underflow traps.

All kind of types pretty useful for economical and cryptographic usages and provide deterministic behavior.

Install

yarn add as-bignum

or

npm i as-bignum

Usage via AssemblyScript

import { u128 } from "as-bignum";

declare function logF64(value: f64): void;
declare function logU128(hi: u64, lo: u64): void;

var a = u128.One;
var b = u128.from(-32); // same as u128.from<i32>(-32)
var c = new u128(0x1, -0xF);
var d = u128.from(0x0123456789ABCDEF); // same as u128.from<i64>(0x0123456789ABCDEF)
var e = u128.from('0x0123456789ABCDEF01234567');
var f = u128.fromString('11100010101100101', 2); // same as u128.from('0b11100010101100101')
var r = d / c + (b << 5) + e;

logF64(r.as<f64>());
logU128(r.hi, r.lo);

Usage via JavaScript/Typescript

TODO

List of types

• u128 unsigned type (tested)
• u256 unsigned type (very basic)
• i128 signed type
• i256 signed type

• safe.u128 unsigned type (tested)
• safe.u256 unsigned type
• safe.i128 signed type
• safe.i256 signed type

• fp128<Q> generic fixed point signed type٭ (very basic for now)
• fp256<Q> generic fixed point signed type٭

• safe.fp128<Q> generic fixed point signed type٭
• safe.fp256<Q> generic fixed point signed type٭

٭ typename Q is a type representing count of fractional bits