tower.js

A Typescript implementation of the Racket numeric tower. This is a rewrite of the js-numbers library by Danny Yoo.

Tower.js is an implementation of the Racket numeric tower in Typescript. It gives you the ability to use exact numbers, complex numbers, and arbitrary precision numbers. This library is based on the js-numbers library, originally written by dyoo.

Example

// factorial.js
import {
    RacketNumber,
    numberToString,
    fromString,
    multiply,
    subtract,
    equals,
    ZERO,
    ONE,
} from 'tower.js';

// Numbers can be Javascript numbers, bigints, or
// tower.js boxed numbers. 

// Javascript numbers are treated as 
// inexact real numbers.
let inexactTwo = 2;

// Javascript bigints are treated as 
// exact integers.
let exactTwo = 2n;

// Numbers can be parsed from strings.
let inexactFive = fromString("5.0");
let exactFive = fromString("5");
let complex = fromString("5+3i");

// Factorial
function factorial(n: RacketNumber): RacketNumber {
    if (equals(n, ZERO)) {
        return ONE;
    }
    return multiply(n, subtract(n, ONE));
}

let result = factorial(exactFive);
console.log(numberToString(result)); // "20"

result = factorial(inexactFive);
console.log(numberToString(result)); // "20.0"

result = factorial(complex);
console.log(numberToString(result)); // "11+27i"

Installation

npm install tower.js@latest

Documentation

Documentation can be found at this repositories Github Pages site.

Bugs and Contributing

Bug reports are appreciated, please open an Issue on this repository. If you'd like to fix an issue or have a contribution to suggest, feel free to open a pull request. If the contribution is large, you should open a draft PR first to suggest it first before writing all of the code.