librarySystem with dependencies

gistfile1.txt

(function(){
	var libraryStorage = {};
	function librarySystem(libraryName, dependencies,callback){
		if (arguments.length===1){
			return libraryStorage[libraryName];
		} else if (arguments.length>1){
			if (dependencies.length===0){
				libraryStorage[libraryName]=callback();
			} else {
			    var dependentLibraries = dependencies.map(function(dependency){
			    	return libraryStorage[dependency];
			    });
				libraryStorage[libraryName]=callback.apply(null, dependentLibraries);
			}
		}
	}
	window.librarySystem=librarySystem;
})();