As simple as JS OO can be; in a tiny package

npm install viral
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Viral is a tiny, pure prototypal OO library for javascript; taking the best parts of boo.

browser support


The most consistent, easiest way to OO in javascript is pure prototypally - and Viral makes this a snap (and packs a tiny punch in the process - < 0.5kb minified).


Viral is a simple base object with two methods:


.extend creates an object that inherits from the object on which it's called, and copies any properties passed to .extend into that new object:

var Person = Viral.extend({
    init: function(firstName, lastName){
        this.firstName = firstName
        this.lastName = lastName
    fullName: function(){ return this.firstName + this.lastName }

// extend is inherited by Person, so we can extend further:
var Coder = Person.extend({
    likesCode: true

Because Viral uses pure prototypal inheritance - objects inheriting directly from objects - Coder and Person are just objects like any other:


//  {
//      init: [Function],
//      fullName: [Function]
//  }


//  {
//      init: [Function],
//      fullName: [Function],
//      likesCode: true
//  }


.make creates an object that inherits from the object on which it's called, and calls the init method of this new object with any arguments you pass in.

// using Coder from the above example:
var hugh = Coder.make('hugh', 'jackson')

hugh.fullName() //= 'hugh jackson'
hugh.likesCode  //= true



npm install viral, then require:

var Viral = require('viral')

// use `Viral` here


include as a script tag:

<!doctype html>
        <script src="libs/viral.min.js"></script>
        // use `Viral` here


include as a script. e.g., from the libs/ folder:

require(['libs/viral.min'], function(Viral){
    // use `Viral` here
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