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nastyox
nastyox

Posted on • Edited on

Rando.js: replacing Math.random()

🙉 What's all the hullabaloo?

There's now a vastly better alternative to JavaScript's built-in Math.random() that will make your life easier. Rando.js helps JavaScript developers code randomness more simply, readably, and securely. Whether you need to find a random int/float between two numbers, pick a random value from an array, choose a random element from your jQuery object, grab a character from a string, toss a coin, or do anything of the like while even preventing repetitions, we've got you covered at a cryptographically strong level. The best part? Our library is extremely lightweight and developer friendly- which means it won't take a toll on your project, and it's uber-simple to implement. Find it online and on GitHub.


⚡ Fast implementation

Step 1: Paste the following script tag into the head of your HTML document:

<script src="https://randojs.com/2.0.0.js"></script>
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Or, use npm:

//Install:
npm i @nastyox/rando.js@2.0.0

//Then, paste this at the top of your JavaScript file:
const randojs = require('@nastyox/rando.js'), rando = randojs.rando, randoSequence = randojs.randoSequence;
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Step 2: Use any of the commands explained at https://randojs.com/ in the document's JavaScript as you like.


🎉 Examples

   rando()                       //a floating-point number between 0 and 1 (could be exactly 0, but never exactly 1)  
   rando(5)                      //an integer between 0 and 5 (could be 0 or 5)  
   rando(5, 10)                  //a random integer between 5 and 10 (could be 5 or 10)  
   rando(5, "float")             //a floating-point number between 0 and 5 (could be exactly 0, but never exactly 5)  
   rando(5, 10, "float")         //a floating-point number between 5 and 10 (could be exactly 5, but never exactly 10)  
   rando(true, false)            //either true or false  
   rando(["a", "b"])             //{index:..., value:...} object representing a value of the provided array OR false if array is empty  
   rando({a: 1, b: 2})           //{key:..., value:...} object representing a property of the provided object OR false if object has no properties  
   rando($("div"))               //{index:..., value:...} object representing a jQuery element from the provided jQuery element set OR false if the provided jQuery element set does not contain any elements  
   rando("Gee willikers!")       //a character from the provided string OR false if the string is empty. Reoccurring characters will naturally form a more likely return value  
   rando(null)                   //ANY invalid arguments return false  
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⇢ Prevent repetitions by grabbing a sequence and looping through it

   randoSequence(5)              //an array of integers from 0 through 5 in random order  
   randoSequence(5, 10)          //an array of integers from 5 through 10 in random order  
   randoSequence(["a", "b"])     //an array of {index:..., value:...} objects representing the values of the provided array in random order  
   randoSequence({a: 1, b: 2})   //an array of {key:..., value:...} objects representing the properties of the provided object in random order  
   randoSequence($("div"))       //an array of {index:..., value:...} objects representing all jQuery elements from the provided jQuery element set in random order  
   randoSequence("Good gravy!")  //an array of the characters of the provided string in random order  
   randoSequence(null)           //ANY invalid arguments return false
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If you find this project helpful, please take a second to bookmark the website/leave it a star on GitHub. Thanks everyone.


Top comments (22)

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mich_cook profile image
mich

This looks quite useful. Given that Math.random() returns a float, what drove your decision to make int the default return type in the numerical instances such as rando(5) and rando(5,10) instead of float? Was it an assumption that most people specifying numbers were looking for ints or something else?

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nastyox1 profile image
nastyox

Thanks! That's a great thought. And yes, that's exactly right. I've seen ints as a much more common use case than floats (excluding [0-1)), so I decided to make that the easier of the two. If you have other thoughts on the project, I'm always interested to hear feedback. You can leave a comment here, DM me on here, or create a pull request on my GitHub.

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waylonwalker profile image
Waylon Walker • Edited

Hot tip, include language after the leading backticks for codeblocks to get food syntax hilighting.

example

result

randoSequence(5)  
   //a random integer between 5 and 10 (could be 5 or 10)  

   randoSequence(5, 10)  
   // an array of integers from 5 through 10 in random order  

   randoSequence(["eeny", "meeny", "miny", "moe"])  
   // array of {index:..., value:...} objects representing the values of the provided array in random order  

   randoSequence({species: "mouse", blind: true, count: 3})  
   // array of {key:..., value:...} objects representing the properties of the provided object in random order  

   randoSequence($("input"))  
   // array of {index:..., value:...} objects representing a jQuery elements from the provided jQuery element set in random order  

   randoSequence("Good gravy!")  
   // the characters of the provided string in random order  

   randoSequence(null)  
   // ANY invalid arguments return false

EDIT 🤣 corrected hot too to hot tip

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adam_cyclones profile image
Adam Crockett 🌀

food syntax 🌭

Unexpected hotdog.
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nastyox1 profile image
nastyox

Nice tip. Thanks :)

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po5i profile image
Carlos V.

Looks promising! Is this library a pseudorandom one like Math.random or is it a true random algorithm?

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mrspartak profile image
Spartak

It is using Math.random, just added sugar around it.
Made a ton prototypes long time ago for such tasks

Array.prototype.getRandom = function () {
    return this[Math.floor(Math.random() * this.length)];
};
console.log( [1, 2, 3].getRandom() )
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krishnakakade profile image
krishna kakade

I added this in my reading list looks interesting 🐱‍🏍❤

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daxsoft profile image
Michael Willian Santos

Amazing! I'll study in how to implement it into my projects. Thank you

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nastyox1 profile image
nastyox

It's been getting some attention, so I upgraded it to a cryptographically secure random now. Thanks for being interested in it from the start.

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rekreanto profile image
rekreanto

Just love the design of the website <3. The combination of sparseness, clarity and slight aliveness/animation is awesome! randojs.com/

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nastyox1 profile image
nastyox

thanks a bunch!!

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andygithubchen profile image
andy chen

Cool !

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theharshsingh profile image
Harsh Singh

I had also created a tiny lib for generating random stuff ( integers, floats, hex colors, shuffling an array, unique IDs, etc. ) for personal use. its called kram.js

github.com/rwbeast/kram

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island_dev profile image
Joey The Dev

Good work! I might use this in a future project.