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Build Status Dependency Status

Sorting directed acyclic graphs, for Node.js, io.js and the browser This was originally done by Marcel Klehr. Why not checkout his original repo?


There are a few ways for installing Toposort. Here are them:

  • Via NPM: npm install toposort-class
  • Via Bower: bower install toposort
  • Via Git: git clone git://
  • Direct download (Minified) for use in the browser


Let's say you have the following dependency graph:

  • Plugin depends on Backbone and jQuery UI Button;
  • Backbone depends on jQuery and Underscore;
  • jQuery UI Button depends on jQuery UI Core and jQuery UI Widget;
  • jQuery UI Widget and jQuery UI Core depend on jQuery;
  • jQuery and Underscore don't depend on anyone.

Now, how would you sort this in a way that each asset will be correctly placed? You'll probably need the following sorting:

  • jQuery, jQuery UI Core, jQuery UI Widget, jQuery UI Button, Underscore, Backbone, Plugin

You can achieve it with the following code, using toposort-class:

var Toposort = require('toposort-class'),
    t = new Toposort();
t.add("jquery-ui-core", "jquery")
 .add("jquery-ui-widget", "jquery")
 .add("jquery-ui-button", ["jquery-ui-core", "jquery-ui-widget"])
 .add("plugin", ["backbone", "jquery-ui-button"])
 .add("backbone", ["underscore", "jquery"]);
/* Will output:
 * ['jquery', 'jquery-ui-core', 'jquery-ui-widget', 'jquery-ui-button', 'underscore', 'backbone', 'plugin']
 * And you're done.


CommonJS (Node.js and io.js):

var Toposort = require('toposort-class'),
    t = new Toposort();

Browser with AMD:

define("myModule", ["Toposort"], function(Toposort) {
    var t = new Toposort();

Browser without AMD:

var t = new window.Toposort();

or whatever global object there is instead of window.


.add(item, deps)

  • {String} item - The name of the dependent item that is being added
  • {Array|String} deps - A dependency or list of dependencies of item

Returns: {Toposort} The Toposort instance, for chaining.


Returns: {Array} The list of dependencies topologically sorted.

This method will check for cyclic dependencies, like "A is dependent of A".


Returns: {Toposort} The Toposort instance, for chaining.

Clears all edges, effectively resetting the instance.


Reference to the Toposort constructor.


MIT License