Dynamic loading of js and css dependencies in DOM

loadDependencies.js

function loadDependencies(deps, callback) {
    var dep = deps.shift();

    if (dep['script'] && typeof(window[dep['lib']]) != dep['loadType'] || 'function') {
        var depScript = document.createElement('script');
        depScript.type = 'text/javascript';
        depScript.src = dep['script'];
        (document.getElementsByTagName('head')[0]).appendChild(depScript);
    }

    if (dep['css']) {
        var depCSS = document.createElement('link');
        depCSS.rel = 'stylesheet';
        depCSS.href = dep['css'];
        (document.getElementsByTagName('head')[0]).appendChild(depCSS);
    }

    if (!deps.length && typeof(callback) != 'undefined') {
        if (depScript) {
            depScript.onload = callback;
        } else {
            callback();
        }
    }

    if (deps.length > 0) {
        if (depScript) {
            depScript.onload = function () {
                loadDependencies(deps, callback);
            };
        } else {
            loadDependencies(deps, callback);
        }
    }
}

// How to use:
var dependencies = [
    {
        lib: 'Handlebars',
        script: 'static/deps/handlebarsjs/handlebars.min.js',
        loadType: 'object'
    }, {
        css: 'static/deps/base.css'
    }
];

loadDependencies(dependencies, function () {
    for (var i in options.templateHelpers) {
        Handlebars.registerHelper(i, options.templateHelpers[i]);
    }
    template = Handlebars.compile(options['preview_template']);
});