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First class dependency objects in ECMAScript Harmony

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My favorite perk of Require.JS is how dependencies are sent as arguments to a factory function. Treating dependencies as first class objects makes much more sense to me than polluting the window object - something that happens too much with other dependency management solutions (I'm looking at you, Steal.JS).

I was curious how I might get this functionality with the next generation of JavaScript - namely, ECMAScript Harmony. No browsers implement Harmony's module system just yet, so pardon the pseudocode.

First class dependency objects via Require.JS

function(helloworld, $){

In this example, helloworld.js and jquery.js are fully loaded first, then passed as objects named helloworld and $, respectively. Once in the factory function, I have free reign over the dependencies' methods, properties, and prototypes.

First class dependency objects via ECMAScript Harmony

module helloworld from '../src/helloworld.js';
module $ from '../lib/jquery.js';

This is the same result as Require.JS - the dependencies are loaded asynchronously (Harmony loads modules at compile time), and the dependencies are nicely encapsulated in their respective first class objects.

As it stands, I find the Require.JS syntax to be more readable. The list of dependencies and their mapping to objects is crystal clear. Since I haven't been able to test ECMAScript Harmony modules in a browser yet, the jury is still out on the pleasures of the new module syntax.

Date posted: February 21, 2012


it should be noted that in your require.js example, without wrapping jquery in a define that returns jQuery, it does pollute the window object, with window.jQuery.

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Tony believes that customers' technology problems can be solved with deep respect, sound data, strong process, and adventurous teams. He uses data-driven methods to improve all stages of the development lifecycle – from design, to beta, to final deployment. With numerous ties to the open-source community, Tony also works to solve client problems faster and more effectively with well-tested open-source solutions.

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