@webbuf/numbers NPM

@webbuf/numbers

@webbuf/numbers is a TypeScript/JavaScript library for working with fixed-size unsigned integers. This library provides support for several unsigned integer types (e.g., U8, U16, U32, U64, U128, U256) and allows users to perform common mathematical operations.

Signed integers and floating-point support are planned for future releases.

Installation

You can install the package from npm:

npm install @webbuf/numbers

Usage

The @webbuf/numbers package provides classes for fixed-size unsigned integers. Each class supports the following features:

Basic arithmetic operations: add, sub, mul, div
BigInt conversion: Convert to and from BigInt
Binary data encoding: Convert to and from big-endian and little-endian formats
Hexadecimal conversion: Convert to and from hexadecimal strings

Importing the Package

import { U8, U16, U32, U64, U128, U256 } from "@webbuf/numbers";

Creating Unsigned Integers

You can create instances from BigInt or number values using the fromBn and fromN static methods, respectively. Note that numbers are automatically converted to BigInt and may lose precision.

const uint8 = U8.fromN(255);
const uint64 = U64.fromBn(1024n);

Converting to BigInt

Use the toBn() method to retrieve the value as a BigInt:

const bigIntValue = uint64.toBn(); // 1024n

Arithmetic Operations

Each class supports basic arithmetic operations such as addition, subtraction, multiplication, and division.

const a = U16.fromN(1000);
const b = U16.fromN(500);
const result = a.add(b); // U16 instance with value 1500

Encoding to and from Buffers

For applications needing binary encoding, use the toBEBuf() and toLEBuf() methods to convert to big-endian and little-endian formats, respectively.

const buffer = uint16.toBEBuf(); // Big-endian representation
const uint16FromBuf = U16.fromBEBuf(buffer); // Reconstructed from buffer

Hexadecimal Representation

Each integer class can convert to and from hexadecimal strings:

const hexString = uint32.toHex(); // Hexadecimal string representation
const uint32FromHex = U32.fromHex(hexString); // Reconstruct from hex

API Documentation

FixedNum (Abstract Class)

The FixedNum abstract class provides a foundation for unsigned integer classes and defines the following core methods and properties:

Constructor: Initializes an instance with a buffer of fixed size.
toBn(): Converts the instance value to BigInt.
add(other: FixedNum): Adds another instance of the same type.
sub(other: FixedNum): Subtracts another instance of the same type.
mul(other: FixedNum): Multiplies by another instance of the same type.
div(other: FixedNum): Divides by another instance of the same type.
toBEBuf(): Returns a big-endian FixedBuf.
toLEBuf(): Returns a little-endian FixedBuf.
toHex(): Returns a hexadecimal string of the value.

U8, U16, U32, U64, U128, U256

Each of these classes extends FixedNum with specific byte lengths:

U8: 8-bit unsigned integer
U16: 16-bit unsigned integer
U32: 32-bit unsigned integer
U64: 64-bit unsigned integer
U128: 128-bit unsigned integer
U256: 256-bit unsigned integer

Example usage:

const uint8 = U8.fromN(42);
const uint16 = U16.fromBn(1000n);
console.log(uint8.toBn()); // 42n
console.log(uint16.toBn()); // 1000n

Future Enhancements

Signed Integer Support: Signed integer classes, allowing the representation of both positive and negative values, are planned for future versions.
Floating-Point Support: IEEE-754 floating-point support will be added to extend the range of numbers.