This code is not owned by EY and EY provides no warranty and disclaims any and all liability for use of this code. Users must conduct their own diligence with respect to use for their purposes and any and all usage is on an as-is basis and at your own risk.

general-number

general-number is a library to perform conversion among different types (eg., BigInt, Hexdecimal String, Binary String, Integer, Decimal, Number, Limbs, UTF8, and Field)

Intermediate result is stored as GeneralNumber Object, eg., GeneralNumber { **value: 123n, **limbBitLength: 0n },GeneralNumber { **value: [ 3n, 24n, 17n, 31n ], **limbBitLength: 5n }.

• Install
• Usage
  • new GN()
  • generalise()
• Developer
  • Test
  • Test with yalc

Install

In your NodeJS project:
npm i @eyblockchain/general-number

Usage

See ./tests/testConversion.js for a comprehensive set of type conversion commands). See ./tests/testFunction.js for a comprehensive set of BigInt arithmetic function commands). See ./tests/testIndex.js for a comprehensive set of GN conversion commands).

new GN()

If passed some value, new GN() will infer the type of that value, and can return conversions of that value through custom getters:

import { GN } from 'general-number';

const myOriginalNumber = '0x12345678';

const myGN = new GN(myOriginalNumber);

console.log(myGN.hex());
// should return hex string "0x12345678"

console.log(myGN.hex(32));
// should return as 32 bytes hex string: "0x0000000000000000000000000000000000000000000000000000000012345678"

console.log(myGN.hex(2));
// should return as 2 bytes hex string: "0x5678"

console.log(myGN.hex(8, 2));
// should return as 2 bytes, padded to 8 bytes hex string: "0x0000000000005678"

console.log(myGN.decimal);
// should return as a decimal number: 305419896

console.log(myGN.integer);
// should return as an integer number: 305419896

console.log(myGN.number);
// should return as a number: 305419896

console.log(myGN.bigint);
// should return as a js BigInt: BigInt(myOriginalNumber):305419896n

console.log(myGN.binary);
// should return as a binary string: "10010001101000101011001111000"

console.log(myGN.binaryArray);
// should return as a binary array: [
//   1, 0, 0, 1, 0, 0, 0, 1, 1,
//   0, 1, 0, 0, 0, 1, 0, 1, 0,
//   1, 1, 0, 0, 1, 1, 1, 1, 0,
//   0, 0
// ]

console.log(myGN.field(256, false));
// should return as a finite field GeneralNumber: (myGN % 256):
//GeneralNumber { __value: 120n, __limbBitLength: 0n }

console.log(myGN.field(256));
// should throw an error: Error: field modulus overflow.
// (myGN is larger than the requested modulus 256)

console.log(myGN.limbs(16));
// should return as GeneralNumber of which the value is limbs:
// GeneralNumber { __value: [ 4660n, 22136n ], __limbBitLength: 16n }

console.log(myGN.limbs(16, 4));
// should return as GeneralNumber of which the value is limbs:

console.log(myGN.utf8);
// should return as an ascii string: "4Vx"

In some circumstances, you may need to get the value of a GeneralNumber object:

import { GN } from 'general-number';

const myOriginalNumber = '10010001101000101011001111000';

// const myGN = new GN(myOriginalNumber); // BAD!!! - this would infer the 'type' as decimal!!!

const myGN = new GN(myOriginalNumber);

console.log(myGN.toBigint);
// should return '0x12345678'

const myGNLimbs = myGN.limbs(2n);
console.log(myGNLimbs.toLimbs);
// should return [
//   1n, 0n, 2n, 0n, 3n, 1n,
//   0n, 1n, 1n, 1n, 2n, 1n,
//   3n, 2n, 0n
// ]

generalise()

Generalise is a powerful function for generalising all values within an object or an array.

🇺🇸 Americans: don't worry, generalize works too!

import { generalise } from 'general-number';

// OBJECTS:

const myObj = {
  key1: '0xf198e3403bdda3a0',
  key2: '17408914224622445472',
};

const myGeneralisedObj = generalise(myObj);

console.log(myGeneralisedObj.key1.hex());
// should return as hex: '0xf198e3403bdda3a0'

console.log(myGeneralisedObj.key2.hex());
// should return as hex: '0xf198e3403bdda3a0'

console.log(myGeneralisedObj.all.hex());
// should return the original object's structure, but all values as hex:
// {
//   key1: '0xf198e3403bdda3a0',
//   key2: '0xf198e3403bdda3a0',
// }

// ARRAYS:

const myArr = ['0xf19a0', '17402'];

const myGeneralisedArr = generalise(myArr);

console.log(myGeneralisedObj[0].decimal);
// should return as number: 989600

console.log(myGeneralisedObj[1].decimal);
// should return as number: 17402

console.log(myGeneralisedObj.all.decimal);
// should return the original array's structure, but all values as number:
// [ 989600, 17402 ]

Notice: .all is a custom property given to generalised objects (and arrays), which enables developers to 'get' all values of the object (or array) as the same 'type' (e.g. as hex in the above example).

generalise() can also be used on nested objects or arrays (including arrays of objects or objects of arrays). Each sub-object will be given its own .all property.

generalise() can also be used instead of new GN() for simple values in all cases (except when passing a value of type limbs). So in the first example, const myGN = generalise(myOriginalNumber); would have been equally valid sytax.

Arithnetic Operations

A set of operation are provided for GeneralNumber, including add, sub, mul, addMod, subMod, mulMod, powMod, dbs, gcd, egcd, lcm, max, min.

import { GN } from 'general-number';

const gnNumber = new GN(333);
const gnLimbs = new GN([4n, 2n], 2n);
const gnUtf8 = new GN('hello');
const gnBinary = new GN('110110');
const gnBigint = new GN(120n);
const gnHex = new GN('0x123');

console.log(gnBigint.add(gnHex));
// should return as GeneralNumber object: GeneralNumber { __value: 411n, __limbBitLength: 0n }
console.log(gnBigint.add(gnHex).add(gnBinary));
// should return as GeneralNumber object: GeneralNumber { __value: 756n, __limbBitLength: 0n }
console.log(gnBigint.sub(gnHex));
// should return as GeneralNumber object: GeneralNumber { __value: -171n, __limbBitLength: 0n }
console.log(gnBigint.mul(gnHex));
// should return as GeneralNumber object: GeneralNumber { __value: 34920n, __limbBitLength: 0n }
console.log(gnBigint.addMod(gnHex, 2n));
// should return as GeneralNumber object: GeneralNumber { __value: 1n, __limbBitLength: 0n }
console.log(gnBigint.addMod(gnHex, 2n).addMod(gnBinary, 2n));
// should return as GeneralNumber object: GeneralNumber { __value: 1n, __limbBitLength: 0n }
console.log(gnBigint.subMod(gnHex, 2n));
//should return as GeneralNumber object: GeneralNumber { __value: 1n, __limbBitLength: 0n }
console.log(gnBigint.subMod(gnHex, 2n).subMod(gnBinary, 2n));
//should return as GeneralNumber object: GeneralNumber { __value: 1n, __limbBitLength: 0n }
console.log(gnBigint.mulMod(gnHex, 2n));
//should return as GeneralNumber object: GeneralNumber { __value: 0n, __limbBitLength: 0n }
console.log(gnBigint.mulMod(gnHex, 2n).mulMod(gnBinary, 2n));
//should return as GeneralNumber object: GeneralNumber { __value: 0n, __limbBitLength: 0n }
console.log(gnNumber.powMod(gnLimbs, 5n));
//should return as GeneralNumber object: GeneralNumber { __value: 4n, __limbBitLength: 0n }

const gnBigint1 = new GN(-120n);
console.log(gnBigint1.abs());
//should return as GeneralNumber object: GeneralNumber { __value: 120n, __limbBitLength: 0n }
console.log(gnBigint.gcd(gnHex));
//should return as GeneralNumber object: GeneralNumber { __value: 3n, __limbBitLength: 0n }
console.log(gnBigint.lcm(gnHex).toBigint);
//should return as BigInt number: 11640n
const gnBigint2 = new GN(120n);
const gnBigint3 = new GN(1n);
console.log(gnBigint3.max(gnBigint2));
//should return as GeneralNumber object: GeneralNumber { __value: 120n, __limbBitLength: 0n }
const gnNumber2 = new GN(333333);
console.log(gnBigint.min(gnNumber2));
//should return as GeneralNumber object: GeneralNumber { __value: 120n, __limbBitLength: 0n }

Developer

Test

Clone the repo. npm i
npm test

Test with yalc

If you've made local changes to this repo, and would like to test whether those (unpublished) changes will work with some dependent zkp appliation (zApp)...

...then you’ll need to install your local, ‘branched’ version of general-number in your zApp.

cd path/to/general-number/
yalc publish

You should see something like "@eyblockchain/[email protected] published in store.". Notice the ‘signature’ 3df45b8c .

cd path/to/your/zApp/

Remove the package-lock.json and the node_modules from your zApp's root (if they exist on your machine).

Then:

yalc add @eyblockchain/general-number

You’ll see that this has ‘swapped-in’ the ‘published’ (yalc version) of general-number in the package.json. It’s also created .yalc.lock (which shows that you’ve replaced the ‘proper’ npm package of general-number with your ‘yalc version’ (see the signature field in this file, which should match the signature from earlier)).

Now install node modules:

npm i

If your zApp runs in a container, then you might need to also edit its dockerfile:

Change a line in <your zApp>/Dockerfile from RUN npm ci to RUN npm install.

Add a line in <your zApp>/docker-compose.yml:

yourService:
  build:
    context: .
    dockerfile: Dockerfile
volumes:
  - ./.yalc:/app/.yalc # <<< ADD THIS LINE (or something similar)!!!

When you're happy that your local changes to general-number work and you wish to create a PR, you MUST remove any references to yalc, or the PR shouldn't be accepted.