Why Does the mageUtils module Directly Call require

Question

In Magento 2, there's a mageUtils RequireJS module alias that points to mage/utils/main. If you look at the source of this module

#File: vendor/magento/magento2-base/lib/web/mage/utils/main.js

define(function (require) {
    'use strict';

    var utils = {},
        _ = require('underscore');

    return _.extend(
        utils,
        require('./arrays'),
        require('./compare'),
        require('./misc'),
        require('./objects'),
        require('./strings'),
        require('./template')
    );
});

You can see this code directly calls require to pull in dependencies rather than listing them as define dependencies. I'd expect to see something more like this

define(['./arrays',
        './compare',
        './misc',
        './objects',
        './strings',
        './template'], function (Arrays, Compare, Misc, Objects, Strings, Template) {
    'use strict';

    var utils = {},
        _ = require('underscore');

    return _.extend(
        utils, Arrays, Compare, Misc, Objects, Strings, Template
    );
});

It's my understanding that directly calling require or requirejs to fetch a module reference only works if the module's already been loaded. Therefore, this means the mage/utils/main module can only be used if it's loaded in a particular order as part of the Magento bootstrap process.

1. Is this an incorrect assumption about directly calling require?
2. Is there a technical reason the mage/utils/main utility doesn't use define dependencies to pull these modules in?

Answer 1

This is "simplified CommonJS wrapping". A special form of RequireJS module declaration. In this case require calls are parsed by RequireJs and executed before this function is executed.

Some links:

• http://requirejs.org/docs/api.html#cjsmodule
• http://requirejs.org/docs/whyamd.html#sugar

We discourage it in new code