Gist related to my "Writing modular JavaScript without polluting the global namespace" blogpost on http://marcofranssen.nl

_jsShop.product.js

; (function(jsShop, window, document, undefined) {
    var product = jsShop.product = jsShop.product || (function() {
        //an implementation like shoppingCart
    }());
}(window._jsShop = window._jsShop || {}, window, document));

_jsShop.shoppingCart.js

; (function(jsShop, window, document, undefined) {
    var product = jsShop.product;
    var shoppingCart = jsShop.shoppingCart = jsShop.shoppingCart || (function() {
        var items = [];
        var priceTotal = 0;
    
        var addProduct = function(product) {
            items.push(product);
            updatePriceTotal();
        };
    
        var removeProduct = function(product) {
            //remove product from items
            updatePriceTotal();
        };

        var updatePriceTotal = function() {
            //logic to update the priceTotal
            //use public functions on product to get the price of products
        };
        
        return {
            addProduct: addProduct,
            removeProduct: removeProduct 
        }
    }());
}(window._jsShop = window._jsShop || {}, window, document));

product.js

var product = (function() {
    //an implementation like shoppingCart
}());

shoppingCart.js

var shoppingCart = (function() {
    var items = [];
    var priceTotal = 0;

    var addProduct = function(product) {
        items.push(product);
        updatePriceTotal();
    };

    var removeProduct = function(product) {
        //remove product from items
        updatePriceTotal();
    };

    var updatePriceTotal = function() {
        //logic to update the priceTotal
        //use public functions on product to get the price of products
    };
    
    return {
        addProduct: addProduct,
        removeProduct: removeProduct 
    }
}());

wrapperWithJquery.js

; (function($, jsShop, window, document, undefined) {
    var yourModule = jsShop.yourModule = jsShop.yourModule || (function(){
        //your module code
        $('#shoppingCatTotalPrice').html('€ 8,75');
    }());
}(jQuery, window._jsShop = window._jsShop || {}, window, document));