npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

uint32

v0.2.1

Published

a javascript library for dealing with (bitwise) uint32 operations

Downloads

7,345

Readme

uint32

An uint32 library for javascript.

WHAT??

Javascript has c like binary operators, but within c you normally use the operators on unsigned ints. In javascript all operators work on SIGNED ints. So the operators do always a signed int conversion, which may have some astonishing side effects:

    var x = 0xFFFFFFFF;
    ~~x === x;      // false! ~~x -> -1
    (x | 0) === x;  // false! x | 0 -> -1
    (x & x) === x;  // false! x & x -> -1
    (x ^ 0) === x;  // false! x ^ 0 -> -1
    (x >> 0) === x; // false! x >> 0 -> -1
    (x << 0) === x; // false! x << 0 -> -1

All these samples are clear counter examples of "Principle of Least Astonishment", see http://en.wikipedia.org/wiki/Principle_of_least_astonishment

If You ever wrote "/*jshint bitwise:false*/" (allowing bitwise operations), You should know, when the above pitfalls happen.

Getting

npm install uint32

or building for your own

git clone https://github.com/fxa/uint32.js.git
cd uint32.js
npm install
npm test
tests.html

Feel free to include uint32.js within your other js sources and minify it together with your code. This library has only about 50 effective lines of code... Feel free to copy&paste the code.

API

The API is very unspectacular. The main thing is, it works as you expect, and that is much more than you get calling javascript binary operators directly.

    //
    // importing
    // 
    
    // within node
    var uint32 = require('uint32');
    
    // within browser
    <script src="/path/to/uint32.js"></script>
    <script type="text/javascript">
        var uint32 = window.uint32;
    </script>

    // Creating and Extracting
    uint32.fromBytesBigEndian(1,2,3,4); // 0x01020304
    uint32.getByteBigEndian(0x01020304, 0); // 1
    uint32.toHex(1); // '00000001'
    uint32.toHex(1, 4); // '0001'
    uint32.toUint32(-1); // 0xffffffff
    uint32.highPart(0x0102030405); // 1
    
    // Bitwise Logical Operators    
    uint32.and(1, 3, 5); // 1    
    uint32.or(1, 3, 5); // 5
    uint32.xor(1, 3, 5); // 7
    uint32.not(1); // 0xfffffffe

    // Shifting and Rotating
    uint32.shiftLeft(0x40000000, 1); // 0x80000000
    uint32.shiftRight(0x80000000, 1); // 0x40000000
    uint32.rotateLeft(0x80000000, 1); // 0x00000001
    uint32.rotateRight(0x00000001, 1); // 0x80000000

    // Logical Gates     
    uint32.choose(0x01010202, 0x00010001, 0x01000100); // 0x00010100 
    uint32.majority (0x01, 0x00, 0x01); // 0x01

    // Arithmetic
    uint32.addMod32(0x80000001, 0x80000001); // 2
    uint32.log2(0xffffffff); // 31
    var result = new Uint32Array(2);
    uint32.mult(0xffffffff, 0xffffffff, result); // result -> [0xfffffffe, 0x00000001]
    
    // That's all! 
    // Detailed specifications are in the tests!

License

Do, what You want. This library was designed to be a copy/paste template. It would be nice to hear from You, if You used this library or if You just copy/pasted some source. It would be nice, if you added a "contains code of Franz X Antesberger" or something like that or a ref to the github project to your license information or elsewhere.