Async jQuery loader + script dependency resolver. Including this will asynchronously load jQuery, and allow other scripts to register functions to be called once jQuery is available. Importantly, you can safely use the "async" attribute when referencing this script. Dependency resolution is handled by passing the loaded functions an on-demand ge…

example.js

// each file needs to start with this to make sure the async array/object exists:
var async = async || [];

// these blocks could be in any order or different files:
async.push(function($, loaded) {
	// loaded(name) returns a $.Deferred object, which modules can wait on or resolve as appropriate.
	loaded("C").then(function(C) {
		console.log("loaded A, needed "+C);
		loaded("A").resolve("apple");
	});
});

async.push(function($, loaded) {
	$.when(loaded("A"), loaded("C")).then(function(A, C) {
		console.log("loaded B, needed "+A+" and "+C);
		loaded("B").resolve("banana");
	});
});

async.push(function($, loaded) {
	console.log("loaded C");
	loaded("C").resolve("cherry");
});

loader.js

/* Public domain, no rights reserved. */
var async = async || [];
(function() {
	var JQUERY_URL = "//code.jquery.com/jquery-1.11.0.min.js";

	var script = document.createElement("script");
	script.src = JQUERY_URL;
	script.onload = function() {
		jQuery(function($) {
			
			var loadMap = {};
			function loaded(name) {
				if(loadMap[name]) return loadMap[name];
				loadMap[name] = $.Deferred();
				return loadMap[name];
			}
			
			var queue = async;
			async = {
				push: function(callback) {
					callback($, loaded);
				}
			};
			
			$.each(queue, function(i, callback) {
				callback($, loaded);
			});
		});
	};
	document.head.appendChild(script);
	
})();