Extend everything.

Usage no npm install needed!

<script type="module">
  import jsNpmSuper from 'https://cdn.skypack.dev/@js-npm/super';


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Super is available for both server-side and the browser.


Package is available through npm:

npm install @js-npm/super

Getting Started

It can be used is a replacement for node's util.inherits. Especially useful when building modules for both node and the browser.

const inherits = require('super');

// Classes, actually it uses util.inherits.

const EventEmitter = require('events').EventEmitter;
function Foo() {};

inherits(Foo, EventEmitter);
let foo = new Foo;

console.log(foo instanceof EventEmitter); // true
console.log(Foo.super_ == EventEmitter); // true

It can also be used for simple merging or cloning of objects.

// merge
const   foo = { bar: 'baz' },
        bar = { foo: 3 },
        baz = inherits(bar, foo);


// clone
const   bar = { foo: 3 },
        barClone = clone(bar);

And finally, it also provides a helper that will allow for object to easily be extended, similiar to the style in Backbone.js.

function Foo () {
  this._constructed = true;
  if (this.initialize) this.initialize();

Foo.extend = inherits.extend;

const Bar = Foo.extend({
  initialize: function () {
    this._isBar = true;

const   foo = new Foo(),
        bar = new Bar();

console.log(foo._constructed); // true
console.log(bar._constructed); // true
console.log(foo._isBar); // undefined
console.log(bar._isBar); // true



make test


make test-node


make test-browser

Test coverage:

make coverage


Apache License

Copyright (c) 2020 Alex alex@webz.asia

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at


Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.